Editing Two-party system

{{Short description|Government system dominated by only two major political parties}}
{{Use mdy dates|date=December 2020}}
{{Party politics}}
{{Politics sidebar}}
{{Redirect|Two-party state|telephone call recording laws and notification and requirements|Telephone call recording laws#Two-party consent states}}
A '''two-party system''' is a [[Politics|political]] [[party system]] in which two [[major party|major]] [[political parties]]{{efn|Note: in the politics of [[Australia]], there are not two [[Political party|political parties]] but rather "two major political groupings"; for further information, see [[Coalition (Australia)|the Australian Coalition]].}} consistently dominate the political landscape. At any point in time, one of the two parties typically holds a majority in the [[legislature]] and is usually referred to as the ''majority'' or ''governing party'' while the other is the ''minority'' or ''opposition party.'' Around the world, the term is used to refer to one of two kinds of party systems. Both result from [[Duverger's law]], which demonstrates that [[Winner-take-all system|"winner-take-all" or "first-past-the-post" elections]] produce two dominant parties over time.<ref>Wong Chin Huat, fz.com, July 29, 2013, [http://www.malaysia-today.net/mtcolumns/guest-columnists/58472-when-winner-takes-all When winner takes all] {{Webarchive|url= https://web.archive.org/web/20130801054909/http://www.malaysia-today.net/mtcolumns/guest-columnists/58472-when-winner-takes-all |date=2013-08-01 }}, Accessed August 12, 2013, "...This "winner-takes-all" characteristic of political contestation then forces political groups to consolidate into two blocs, hence, the two-party system..."</ref><ref name="Regis">Regis Publishing, [https://web.archive.org/web/20041102031344/http://academic.regis.edu/jriley/215%20Winner%20Take%20all.htm The US System: Winner Takes All], {{Dead link|date=January 2019}} Accessed August 12, 2013, "...Winner-take-all rules trigger a cycle that leads to and strengthens a system of few (two in the US) political parties..." ([https://web.archive.org/web/20131029200749/http://academic.regis.edu/jriley/215%20Winner%20Take%20all.htm in Wayback Machine])</ref>

The first type of ''two-party system'' is an arrangement in which all (or nearly all) [[Official|elected official]]s belong to one of two major parties. In such systems, [[minor party|minor]] or [[Third party (politics)|third parties]] rarely win any seats in the legislature. Such systems exist, for example, in the [[Politics of the United States|United States]], [[Politics of the Bahamas|the Bahamas]], [[Politics of Jamaica|Jamaica]], and [[Politics of Zimbabwe|Zimbabwe]].<ref name=SchmidtTextbook/><ref name=Boundless>The Two Party System, Boundless Publishing, [https://www.boundless.com/political-science/interest-groups/the-two-party-system/the-two-party-system/ Two-party systems are prominent in various countries, such as the U.S., and contain both advantages and disadvantages] {{Webarchive|url=https://web.archive.org/web/20131003082455/https://www.boundless.com/political-science/interest-groups/the-two-party-system/the-two-party-system/ |date=2013-10-03 }}, Accessed August 12, 2013 "...There are two main reasons winner-takes-all systems lead to a two-party system...",</ref><ref name=EricBlack>Eric Black, Minnpost, October 8, 2012,  [http://www.minnpost.com/eric-black-ink/2012/10/why-same-two-parties-dominate-our-two-party-system Why the same two parties dominate our two-party system] {{Webarchive|url=https://web.archive.org/web/20200502173118/https://www.minnpost.com/eric-black-ink/2012/10/why-same-two-parties-dominate-our-two-party-system/ |date=2020-05-02 }}, Accessed August 12, 2013, "...SMDP (single-member districts, plurality) voting system. ... This forces those who might favor a minor party candidate to either vote for whichever of the two biggest parties the voter dislikes the least, or to risk the likelihood that their vote will be "wasted" or, worse, that they will end up helping the major-party candidate whom the voter dislikes the most to win. Minor parties aren't banned, but they seldom produce a plurality winner, and their lack of success often causes the minor parties to wither and die...."</ref><ref>History Learning Site, [http://www.historylearningsite.co.uk/america_two_party.htm Why America is a two-party state] {{Webarchive|url=https://web.archive.org/web/20150608005137/http://www.historylearningsite.co.uk/america_two_party.htm |date=2015-06-08 }}, Accessed August 12, 2013, "...The American electoral system – winner-takes-all – guarantees that any third, fourth party etc has no chance of winning...."</ref> In such systems, while chances for third-party candidates winning election to major national office are remote, it is possible for [[Political faction|factions within the larger parties]] to exert influence on one or even both of the two major parties.<ref name=Cato>Patrick Bashan, CATO Institute, June 9, 2004, [http://www.cato.org/publications/commentary/do-electoral-systems-affect-government-size Do Electoral Systems Affect Government Size?] {{Webarchive|url=https://web.archive.org/web/20200310053214/https://www.cato.org/publications/commentary/do-electoral-systems-affect-government-size |date=2020-03-10 }}, Accessed August 12, 2013, "...The current system has many disadvantages, most notably its propensity to discriminate against minor parties operating outside the increasingly uncompetitive, cozy two-party system.... America's winner-takes-all electoral system may be the least bad option for those seeking to limit government involvement in the nation's economic life...."</ref><ref>George F. Will, October 12, 2006, Washington Post, [https://www.washingtonpost.com/wp-dyn/content/article/2006/10/11/AR2006101101597.html From Schwarzenegger, a Veto for Voters' Good] {{Webarchive|url=https://web.archive.org/web/20170520214400/http://www.washingtonpost.com/wp-dyn/content/article/2006/10/11/AR2006101101597.html |date=2017-05-20 }}, Accessed August 12, 2013, "...That electoral vote system (combined with the winner-take-all allocation of votes in all states but Maine and Nebraska) makes it very difficult for third-party presidential candidates to be competitive..."</ref><ref>Ashley Ford, September 17, 2012, Cavalier Daily, [http://www.cavalierdaily.com/article/2010/09/party-of-three Party of three: A third political party is an important aspect of the Virginia democratic process] {{Webarchive|url=https://web.archive.org/web/20200323213921/https://www.cavalierdaily.com/article/2010/09/party-of-three |date=2020-03-23 }}, Accessed August 12, 2013, "...The two party system forces the third party to join their group in a winner take all system..."</ref><ref name=PBS>Two Party System, PBS, [https://www.pbs.org/independentlens/unreasonableman/twoparty.html Two-Party System] {{Webarchive|url=https://web.archive.org/web/20191117160544/http://www.pbs.org/independentlens/unreasonableman/twoparty.html |date=2019-11-17 }}, Accessed August 12, 2013, "...Third-party or independent candidates face a slew of obstacles in American politics, from limited media coverage to legal barriers and Congressional leadership rules. Laws regarding third-party candidates also vary from state to state, presenting additional difficulties...."</ref><ref name=Cillizza/><ref name=Cillizza2>Chris Cillizza and Aaron Blake, May 18, 2012, The Washington Post, [https://www.washingtonpost.com/blogs/the-fix/post/americans-elect-and-the-death-of-the-third-party-movement/2012/05/17/gIQAIzNKXU_blog.html Americans Elect and the death of the third party movement] {{Webarchive|url=https://web.archive.org/web/20200225212329/https://www.washingtonpost.com/blogs/the-fix/post/americans-elect-and-the-death-of-the-third-party-movement/2012/05/17/gIQAIzNKXU_blog.html |date=2020-02-25 }}, Accessed August 11, 2013</ref>

''Two-party system'' also indicates an arrangement, common in [[Parliamentary system|parliamentary systems]], in which two major parties dominate elections, but in which there are viable minor parties and/or [[Independent politician|independents]] regularly elected to the legislature. These successful minor parties are often [[Regionalism (politics)|regional parties]]. In these systems, the two major parties exert proportionately greater influence than their percentage of voters would suggest, and other parties may frequently win election to [[Local government|local]] or [[Administrative division|subnational]] office.<ref>{{cite book |url=https://books.google.com/books?id=Cm5a9X0hpyUC&q=two+party+system |title=The Tyranny of the Two-Party System |via=Google Books |access-date=2012-10-29 |isbn=978-0231110358 |year=2002 |last1=Disch |first1=Lisa Jane |publisher=Columbia University Press |archive-date=2011-12-26 |archive-url=https://web.archive.org/web/20111226094322/http://books.google.com/books?id=Cm5a9X0hpyUC&printsec=frontcover&dq=two+party+system |url-status=live }}</ref> [[Canada]], the [[United Kingdom]], and [[Politics of Australia|Australia]] are examples of countries that have this kind of two-party system.   

== Europe ==
=== Malta ===
{{Main|Politics of Malta}}
[[Politics of Malta|Malta]] is somewhat unusual in that while the electoral system is [[single transferable vote]] (STV), a form with proportional representation traditionally associated with a multi-party system, minor parties have not had much success. Politics is dominated between the centre-left [[Labour Party (Malta)|Labour Party]] and the centre-right [[Nationalist Party (Malta)|Nationalist Party]], with no third parties winning seats in Parliament between [[1962 Maltese general election|1962]] and [[2017 Maltese general election|2017]] and since 2022.<ref>{{cite news |last1=Borg |first1=Bertrand |date=6 June 2017 |title=Marlene Farrugia's election met with counting hall taunts |url=https://www.timesofmalta.com/articles/view/20170606/local/marlene-farrugia-elected-on-10th-district.650090 |url-status=live |archive-url=https://web.archive.org/web/20180924175547/https://www.timesofmalta.com/articles/view/20170606/local/marlene-farrugia-elected-on-10th-district.650090 |archive-date=24 September 2018 |access-date=9 June 2017 |work=Times of Malta |quote=Malta's next legislature will feature an elected third party representative for the first time in more than 50 years, with Democratic Party leader Marlene Farrugia having made it into parliament.}}</ref>
<!--===Russia ===
Post-Soviet Russia was close to having a competitive two-party system in 1999 when two "[[party of power|parties of power]]" (specifically, socio-political associations and [[parliamentary group|parliamentary factions]]) were formed in the [[3rd State Duma]] – [[Unity (Russian political party)|Unity]] and [[Fatherland – All Russia]]. However, by the end of 2001, both had united into one pro-presidential party – [[United Russia]].

On 24 March 2006, a meeting was held between the [[:ru:Заместитель руководителя Администрации президента России|deputy head of the presidential administration]], [[Vladislav Surkov]], and the chairman of the [[Russian Party of Life]], [[Sergey Mironov]], and 30 deputies from the Russian Party of Life. At the meeting, Surkov first openly formulated the idea of building a two-party system in the country, in which, depending on the circumstances, the Kremlin could rely on one of the two system-forming parties.<ref name="kommersant">«Коммерсант»: [http://www.kommersant.ru/doc/697936 ''«Стенограмма-минимум. Партия жизни обнародовала инструкции Владислава Суркова»''] {{webarchive|url=https://web.archive.org/web/20110527051012/http://www.kommersant.ru/doc/697936|date=20110527051012}}, № 150 (3481), 16.08.2006.</ref> Surkov described the problem as follows: "Society does not have a "second leg" that it can shift to when the first one goes numb. Russia needs a second major party," which, according to the [[Presidential Administration of Russia|presidential administration]]'s plan, should, in the future, gain the votes that are currently collected by parties "of a [[left-wing politics|leftist bias]] and with a strong [[Russian nationalism|nationalist]] flavor." At the same time, Surkov left the role of the "main leg" for the coming years to United Russia: "The largest party, around which the political process will be built for a considerable time, in my opinion, of course, should be United Russia." Vladislav Surkov advised Russian Party of Life activists to rely on the protest electorate rather than on administrative resources: "It is better that this [protest] electorate, which is opposed to all types of administration, will be attracted to you than to destructive forces." A transcript of the meeting was published on 16 August 2006.<ref name="kommersant" /><ref>[https://web.archive.org/web/20070707165914/http://rpvita.ru/activity/opinion/5009.html ''«Встреча группы депутатов от Российской партии Жизни с заместителем Руководителя Администрации Президента Российской Федерации — помощником Президента Российской Федерации В. Ю. Сурковым»'', 24 марта 2006 года], стенограмма опубликована на сайте партии 16.08.2006.</ref>

The [[A Just Russia]] party, which emerged in 2006, with some support from President [[Vladimir Putin]], positioned itself as a competitor to United Russia within the framework of a potential two-party system.

However, as a result of the fact that during the [[2007 Russian legislative election|Duma elections of 2007]], Putin politically headed the United Russia party, which won an absolute victory in the elections, by the end of 2007, a [[dominant-party system]] had emerged in Russia, in which United Russia has a [[supermajority|constitutional qualified majority]] in the Duma.-->
<!--Russia is not a two-party system-->

=== Spain ===
{{Main|Political parties in Spain}}
A report in ''[[The Christian Science Monitor]]'' in 2008 suggested that [[Spain]] was moving toward a "greater two-party system" while acknowledging that Spain has many small parties.<ref name="twsNovGb">{{cite news |author=Robert Marquand |date=March 11, 2008 |title=In Spain's elections, Socialists win with liberal appeal |url=http://www.csmonitor.com/World/2008/0311/p07s03-wogn.html |url-status=live |archive-url=https://web.archive.org/web/20101107105432/http://www.csmonitor.com/World/2008/0311/p07s03-wogn.html |archive-date=2010-11-07 |access-date=2010-11-07 |newspaper=Christian Science Monitor |quote=The outcome also suggests that Spain, which has many small parties, is moving toward a greater two-party system – even as basic splits between right and left are deepening and becoming more contentious.}}</ref> A 2015 article published by ''[[WashingtonPost.com]]'' written by academic Fernando Casal Bértoa noted the decline in support for the two main parties, the [[People's Party (Spain)|People's Party]] (PP) and the [[Spanish Socialist Workers' Party]] (PSOE) in recent years, with these two parties winning only 52 percent of the votes in that year's [[2015 Spanish regional elections|regional]] and [[2015 Spanish local elections|local]] elections. He explained this as being due to the [[2008–16 Spanish financial crisis|Spanish economic crisis]], a series of [[Corruption in Spain#Corruption cases in the post-Franco era|political corruption scandals]] and broken campaign promises. He argued that the emergence of the new [[Citizens (Spanish political party)|Citizens]] and [[Podemos (Spanish political party)|Podemos]] parties would mean the political system would evolve into a two-bloc system, with an alliance of the PP and Citizens on the right facing a leftist coalition of PSOE, Podemos and the [[United Left (Spain)|United Left]].<ref>{{cite web |last=Casal Bértoa |first=Fernando |date=19 June 2015 |title=Shake-up in Spain: Reform parties have broken the old two-party cartel |url=https://www.washingtonpost.com/news/monkey-cage/wp/2015/06/19/shake-up-in-spain-reform-parties-have-broken-the-old-two-party-cartel/ |url-status=live |archive-url=https://web.archive.org/web/20170929001131/https://www.washingtonpost.com/news/monkey-cage/wp/2015/06/19/shake-up-in-spain-reform-parties-have-broken-the-old-two-party-cartel/ |archive-date=29 September 2017 |access-date=23 September 2017 |website=WashingtonPost.com}}</ref> Far-right [[Vox (political party)|Vox]] party became the third largest group in the Spanish parliament in the late 2010s.
=== United Kingdom ===
In countries such as [[Politics of the United Kingdom|Britain]], two major parties which have strong influence emerge and tend to elect most of the candidates, but a multitude of lesser parties exist with varying degrees of influence, and sometimes these lesser parties are able to elect officials who participate in the legislature. In political systems based on the [[Westminster system]], which is a particular style of [[Parliamentary system|parliamentary democracy]] based on the British model and found in many [[British Commonwealth|Commonwealth]] countries, a majority party will form the [[government]] and the minority party will form the [[opposition (politics)|opposition]], and coalitions of lesser parties are possible; in the rare circumstance in which neither party is the majority, a [[hung parliament]] arises. Sometimes these systems are described as ''two-party systems'', but they are usually referred to as ''multi-party'' systems or a ''two-party plus'' system. There is not always a sharp boundary between a two-party system and a multi-party system.

The [[Labour Party (UK)|Labour Party]] and the [[Conservative Party (UK)|Conservative Party]] are the two largest parties in the United Kingdom since [[1922 United Kingdom general election|1922]].
===Poland===
In Poland, the two largest parties since [[2005 Polish parliamentary election|2005]] have been [[Civic Platform]] and the [[Law and Justice]] party.

== North America ==

=== Canada ===
[[Politics of Canada|Canada]] has a multiparty system at the federal and provincial levels. Some provinces have effectively become two-party systems in which only two parties regularly get members elected, while smaller parties largely fail to secure electoral representation, and two of the three territories are run under a non-partisan [[consensus government]] model rather than through a political party system. The provincial legislative assembly of [[Alberta]] currently has only two parties; two-party representation has also historically been common in the legislative assemblies of [[British Columbia]], [[New Brunswick]] and [[Prince Edward Island]], although all did elect some third-party members in their most recent provincial elections.

The [[Liberal Party of Canada]] and the [[Conservative Party of Canada]] are the two largest parties in Canada.

=== Caribbean ===
The [[Commonwealth Caribbean]] while inheriting their basic political and voting system from [[Great Britain]] have become two-party systems. The [[politics of Jamaica]] are between the [[People's National Party]] and the [[Jamaica Labour Party]]. The [[politics of Guyana]] are between the [[People's Progressive Party (Guyana)|People's Progressive Party]] and [[A Partnership for National Unity|APNU]] which is actually a coalition of smaller parties. The [[politics of Trinidad and Tobago]] are between the [[People's National Movement]] and the [[United National Congress]]. The [[Politics of Belize]] are between the [[United Democratic Party (Belize)|United Democratic Party]] and the [[People's United Party]]. The [[Politics of the Bahamas]] are between the [[Progressive Liberal Party]] and the [[Free National Movement]]. The [[politics of Barbados]] are between the [[Democratic Labour Party (Barbados)|Democratic Labour Party]] and the [[Barbados Labour Party]].

=== United States ===
{{Main|Political parties in the United States}}
{{See also|First Party System|Second Party System|Third Party System|Fourth Party System|Fifth Party System|Sixth Party System|Seventh Party System}}{{more citations needed|section|date=December 2019}}

{{Split section|discuss=Talk:Two-party system#United States|date=January 2021}}

The [[Politics of the United States|United States]] has two dominant political parties; historically, there have been few instances in which third party candidates won an election. In the [[First Party System]], only [[Alexander Hamilton]]'s [[Federalist Party]] and [[Thomas Jefferson]]'s [[Democratic-Republican Party]] were significant political parties. Toward the end of the First Party System, the Democratic-Republicans were dominant (primarily under the presidency of [[James Monroe]]).

Under the [[Second Party System]], the Democratic-Republican Party split during the [[1824 United States presidential election]] into Adams' Men and Jackson's Men. In the [[1828 United States presidential election|1828 presidential election]], the modern [[Democratic Party (United States)|Democratic Party]] formed in support of [[Andrew Jackson]]. The [[National Republicans]] were formed in support of [[John Quincy Adams]]. After the National Republicans collapsed, the [[Whig Party (United States)|Whig Party]] and the [[Free Soil Party]] quickly formed and collapsed.

In 1854 the [[Third Party System]] began when the modern [[Republican Party (United States)|Republican Party]] formed from a loose coalition of former Whigs, Free Soilers and other anti-slavery activists. The Republicans quickly became the dominant party nationally, and [[Abraham Lincoln]] became the first Republican President in the [[1860 United States presidential election|1860 presidential election]]. The Democrats held a strong, loyal coalition in the [[Solid South]]. This period saw the [[American Civil War]] where the South (which was mostly dominated by the [[Southern Democrats]]) attempted to secede as the [[Confederate States of America]], in an attempt to preserve [[Slavery in the United States|racial slavery]]. The South lost the war and were forced to [[End of slavery in the United States of America|end slavery]], and during the following [[Reconstruction Era]] the Republicans remained the most popular party nationally while the Democrats remained dominant in the South.

During the [[Fourth Party System]] from about 1896 to 1932, the Republicans remained the dominant presidential party, although Democrats [[Grover Cleveland]] and [[Woodrow Wilson]] were both elected to two terms (non-consecutively in the case of the former).

The [[1932 United States elections]] saw the onset of the [[Fifth Party System]] and a long period of Democratic dominance due to the [[New Deal Coalition]]. Democrat President [[Franklin D. Roosevelt]] won landslides in four consecutive elections. Other than the two terms of Republican [[Dwight Eisenhower]] from 1953 to 1961, Democrats retained firm control of the presidency until the mid-1960s. In Congress, Democrats retained majorities in both houses for 60 years until the [[Republican Revolution]], broken only by brief Republican majorities.

There was a significant change in U.S. politics in 1960,<ref>{{cite book |author1=L. Sandy Maisel |author-link1=L. Sandy Maisel |url=https://books.google.com/books?id=mQlZ0H2zavwC&pg=PA42 |title=Parties and Elections in America: The Electoral Process |author2=Mark D. Brewer |publisher=Rowman & Littlefield |year=2011 |isbn=9781442207707 |edition=6th |page=42 |access-date=2020-05-29 |archive-url=https://web.archive.org/web/20140107201213/http://books.google.com/books?id=mQlZ0H2zavwC&pg=PA42 |archive-date=2014-01-07 |url-status=live}}</ref> and this is seen by some as a transition to a [[Sixth Party System|sixth party system]].

Since the mid-1960s, despite a couple of landslides (such as [[Richard Nixon]] carrying 49 states and 61% of the popular vote over [[George McGovern]] in [[1972 United States presidential election|1972]]; [[Ronald Reagan]] carrying 49 states and 58% of the popular vote over [[Walter Mondale]] in [[1984 United States presidential election|1984]]), presidential elections have been competitive between the predominant Republican and Democratic parties and no one party has been able to hold the presidency for more than three consecutive terms.

Throughout every American party system, no third party has won a presidential election or majorities in either house of Congress. Despite that, third parties and third party candidates have gained traction and support. In the election of [[1912 United States presidential election|1912]], [[Theodore Roosevelt]] won 27% of the popular vote and 88 electoral votes running as a [[Progressive Party (United States, 1912)|Progressive]]. In the [[1992 United States presidential election|1992 presidential election]], [[Ross Perot]] won 19% of the popular vote but no electoral votes running as an Independent.

Modern [[Politics of the United States|American politics]], in particular the [[United States electoral college|electoral college system]], has been described as duopolistic since the Republican and Democratic parties have dominated and framed [[policy]] debate as well as the public discourse on matters of national concern for about a century and a half. [[Third party (United States)|Third Parties]] have encountered various blocks in [[ballot access|getting onto ballots]] at different levels of government as well as other electoral obstacles, such as denial of access to general election debates. Since 1987, the [[Commission on Presidential Debates]], established by the Republican and Democratic parties themselves, supplanted debates run since 1976 by the [[League of Women Voters]]. The League withdrew its support in protest in 1988 over objections of alleged stagecraft such as rules for camera placement, filling the audience with supporters, approved moderators, predetermined question selection, room temperature and others.<ref>{{Cite web |title=Statement by Nancy M. Neuman, President, League of Women Voters &#124; League of Women Voters |date=October 3, 1988 |url=https://www.lwv.org/newsroom/press-releases/statement-nancy-m-neuman-president-league-women-voters |url-status=live |archive-url=https://web.archive.org/web/20191227175105/https://www.lwv.org/newsroom/press-releases/statement-nancy-m-neuman-president-league-women-voters |archive-date=2019-12-27 |access-date=2019-12-27}}</ref> The Commission maintains its own rules for admittance<ref>{{Cite web |title=CNNfyi.com - Nader and Buchanan excluded from first presidential debate - October 3, 2000 |url=http://edition.cnn.com/2000/fyi/news/10/03/debate.omissions/index.html |url-status=live |archive-url=https://web.archive.org/web/20190107072257/http://edition.cnn.com/2000/fyi/news/10/03/debate.omissions/index.html |archive-date=2019-01-07 |access-date=2019-12-27}}</ref> and has only admitted a single third-party candidate to a televised debate, [[Ross Perot]], in [[1992 United States presidential election|1992]].<ref>{{cite news |last=Fain |first=Thom |date=September 26, 2016 |title=What is the Commission on Presidential Debates, and what do they do? |url=https://www.sj-r.com/zz/elections/20160926/what-is-commission-on-presidential-debates-and-what-do-they-do |url-status=live |archive-url=https://web.archive.org/web/20200606214709/https://www.sj-r.com/zz/elections/20160926/what-is-commission-on-presidential-debates-and-what-do-they-do |archive-date=June 6, 2020 |access-date=June 6, 2020 |work=[[The State Journal-Register]] |location=Springfield, Illinois}}</ref>

Some parts of the US have had their own party systems, distinct from the rest of the country.
* In [[Puerto Rico]], there is a [[multi-party system]] with the [[Popular Democratic Party (Puerto Rico)|Popular Democratic Party]] and [[New Progressive Party (Puerto Rico)|New Progressive Party]] being the two strongest parties. Minor parties in the 2021 legislature include the [[Puerto Rican Independence Party]], [[Citizens' Victory Movement]] and [[Project Dignity]].
* In [[Guam]], the [[Popular Party (Guam)|Popular Party]] was the only political party from 1949-1954, and was dominant until 1967 when they became affiliated with the Democrats. Since then, the Democrats and Republicans have been the two main parties.
* In the [[Northern Mariana Islands]], the Democrats and Republicans are the two main parties but as recently as 2013, the Governor was a member of the [[Covenant Party (Northern Mariana Islands)|Covenant Party]].
* In [[American Samoa]], the [[American Samoa Fono]] (territorial legislature) is non-partisan, and on ballots only candidate names are displayed, not political parties. The Governor has typically been either Democrat or Republican.
* In the [[US Virgin Islands]], the Democrats and Republicans have been the main two parties, but two Governors during the 1970s were part of the [[Independent Citizens Movement]], and from 2015-2019 the Governor was an independent.

== Africa ==

=== Ghana ===
The [[Politics of Ghana|Republic of Ghana]] since its [[Democratic transition|transition to democracy]] in 1992 have a strongly institutionalized two-party system led by [[New Patriotic Party]] and [[National Democratic Congress (Ghana)|National Democratic Congress]].<ref>{{cite book |last1=Daddieh |first1=C.K. |last2=Bob-Milliar |first2=G.M. |title=Party Systems and Democracy in Africa |editor1-last=Doorenspleet |editor1-first=R. |editor2-last=Nijzink |editor2-first=L. |publisher=Palgrave Macmillan |location=London |year=2014 |isbn=978-1-137-01171-8 |chapter=Ghana: The African Exemplar of an Institutionalized Two-Party System?  |doi=10.1057/9781137011718_6 |chapter-url=https://doi.org/10.1057/9781137011718_6}}</ref>

=== Zimbabwe ===
The [[politics of Zimbabwe]] are effectively a two-party system between the [[Robert Mugabe]] founded [[Zimbabwe African National Union-Patriotic Front]] and the opposition coalition [[Movement for Democratic Change – Tsvangirai|Movement for Democratic Change]].

==Australia==
{{Main|Political parties of Australia|Two-party-preferred vote}}

===House of Representatives===

Since the 1920s, the [[Australian House of Representatives]] (and thus the [[Federal government of Australia|federal government]]) has in effect been a two-party system.

Since the end of [[World War II]], Australia's House of Representatives has been dominated by two factions:
* the centre-left [[Australian Labor Party]]
* the centre-right [[Coalition (Australia)|Coalition]].

The Coalition has been in government about two-thirds of time, broken by four periods of Labor governments: 1972–1975, 1983–1996, 2007–2013, and since 2022.

The ALP is Australia's largest and oldest continuing political party, formed in 1891 from the [[Australian labour movement]]. The party has branches in every state and territory.

The Coalition refers to the alliance between the [[Liberal Party of Australia]] (Australia's 2nd largest party) and [[National Party of Australia]] (4th largest). It was formed after the [[1922 Australian federal election]], when the [[Nationalist Party (Australia)|Nationalist Party]] (ancestor of today's Liberal Party) lost its absolute majority, and was only able to remain in government by allying with the Country Party (now called the [[National Party of Australia|National Party]]). Under the Coalition agreement, if the Coalition forms government then the [[Prime Minister of Australia|Prime Minister]] will be the leader of the Liberals, and the [[Deputy Prime Minister of Australia|Deputy Prime Minister]] will be the leader of the Nationals. In theory, disagreements between the Coalition's constituent parties would lead to the Coalition splitting apart. This has happened only a few times in Australia's modern political history, and has always resulted in the Coalition coming back together by the next election. The most recent split occurred in 2025, following [[2025 Australian federal election|Labor's landslide victory]] at that year's election.<ref>{{cite web | url=https://www.abc.net.au/news/2025-05-20/nationals-will-not-re-enter-coalition-agreement/105313818 | title=Nationals call it quits on decades-long coalition with Liberals | work=ABC News }}</ref><ref>https://www.theguardian.com/australia-news/2025/may/20/nationals-leaving-split-coalition-liberal-party-australian-election></ref><ref>{{cite web | url=https://theconversation.com/nationals-break-the-coalition-in-a-major-blow-to-sussan-ley-256455 | title=Nationals break the Coalition, in a major blow to Sussan Ley }}</ref>

One reason for Australia's two-party system is because the House of Representatives (which chooses the [[Prime Minister of Australia]]) is elected through the [[instant-runoff voting]] electoral system. Although voters can preference third parties and independents above the major parties, and the voting method has a reduced [[spoiler effect]], there is still only one member per electoral division (ie: a winner-take-all system) and so major parties tend to win the vast majority of seats even if they need to rely on preferences to do so. For example, a Labor candidate may win a seat with 30% of the vote for Labor and 21% from [[Australian Greens]] voters who ranked Labor second.

===Senate===

On the other hand, the [[Australian Senate]] is effectively a multi-party system, and a Senate majority matching the House is very rare. It uses [[single transferable vote]] with multiple Senators for each state/territory. This results in rough [[proportional representation]] and as a result, third parties have much more influence and often hold the [[Balance of power (parliament)|balance of power]]. Since 2004, the [[Australian Greens]] have been the third largest party in the country, with 8-13% of the national vote and an equivalent amount of Senators. Prior to this, the [[Australian Democrats]] was the third largest party. Other current and past parties include [[One Nation (Australia)|One Nation]], the [[Liberal Democratic Party (Australia)|Liberal Democrats]] and [[Family First Party|Family First]].

Some Australian states have seen the rise of minor parties at either the state or federal level (eg: [[Centre Alliance]] in [[South Australia]], [[Katter's Australian Party]] in northern [[Queensland]], and the [[Shooters, Fishers and Farmers Party]] in western New South Wales), while some have seen long periods of dominance by one party. Some parties are absent entirely in parts of the country.
* The [[Australian Capital Territory]] has had a [[Australian Labor Party (Australian Capital Territory Branch)|Labor]]/[[ACT Greens|Greens]] coalition government since 2012, opposed by the [[Liberal Party of Australia (A.C.T. Division)|Liberals]] (Nationals not present). Labor was in government alone from 2001-2012.
** Notably, the ACT is the only state/territory where the Greens have been in power.
* In the [[Northern Territory]], the two main parties are [[Australian Labor Party (Northern Territory Branch)|Labor]] and the [[Country Liberal Party]] (CLP), which aligns with the Coalition at the federal level.
* In [[Western Australia]], the [[Liberal Party of Australia (Western Australian Division)|Liberal]] and [[National Party of Australia (WA)|National parties]] are not in a permanent coalition at the state level. At the [[2021 Western Australian state election]] [[Australian Labor Party (Western Australian Branch)|Labor]] won 53 out of 59 lower house seats in a landslide victory. The National Party won 4 seats making them the official opposition. The Liberals won only 2 seats, putting them on the [[crossbench]].
* In [[New South Wales]] and [[Victoria (Australia)|Victoria]], the main parties reflect the situation nationally: Labor versus the Coalition of the Liberals and Nationals. NSW is the only state where the Coalition has never split, but has also never merged into one party.
* In [[South Australia]] and [[Tasmania]], the main parties are Labor and the Liberals, with the Nationals not holding any seats.
* In [[Queensland]], the main parties are [[Australian Labor Party (Queensland Branch)|Labor]] and the [[Liberal National Party of Queensland|Liberal-National Party]] (LNP). Historically, the Country Party was the largest Coalition member and they governed the state from 1957 until 1989. This was partially due to a [[malapportionment]] which heavily favoured rural seats. It had been originally designed by a Labor government, but ended up benefitting the Country Party as demographics shifted. Later, Premier [[Joh Bjelke-Petersen]] increased his power by using [[Queensland Police]] to suppress political dissent, and enacted the [[Bjelkemander]], worsening malapportionment in order to reduce the power of the Liberals so his Country Party could rule alone. Eventually, media reports and the [[Fitzgerald Inquiry]] revealed wide-ranging corruption police and government. Bjelke-Petersen was forced to resign in disgrace, while many high-ranking police and politicians were criminally charged. Labor has been in power for most of the time since then, with the state Country and Liberal parties merging into the LNP, which is a member of the Coalition federally.

==Latin America==
Most Latin American countries also have [[presidential systems]] very similar to the US often with [[Winner-Take-All Politics|winner takes all]] systems. Due to the common accumulation of power in the presidential office both the official party and the main opposition became important political protagonists causing historically two-party systems.<ref>{{cite journal|last1=Coppedge|first1=Michael|title=The Dynamic Diversity of Latin American Party Systems|journal=Kellogg Institute, Hesburgh Center}}</ref> Some of the first manifestations of this particularity was with the [[Liberalism and conservatism in Latin America|liberals and conservatives]] that often fought for power in all Latin America causing the first two-party systems in most Latin American countries which often lead to civil wars in places like [[Colombia]], [[Ecuador]], [[Mexico]], [[Venezuela]], the [[Federal Republic of Central America|Central American Republic]] and [[Peru]], with fights focusing specially on opposing/defending the privileges of the [[Catholic Church]] and the [[Creole peoples|creole]] [[aristocracy]]. Other examples of primitive two-party systems included the [[Pelucones]] versus [[Pipiolos]] in [[Chile]], [[Federalist Party (Argentina)|Federalists]] versus [[Unitarian Party|Unitarians]] in [[Argentina]], [[Colorado Party (Paraguay)|Colorados]] versus [[Authentic Radical Liberal Party|Liberals]] in [[Paraguay]] and [[Colorado Party (Uruguay)|Colorados]] versus [[National Party (Uruguay)|Nationals]] in [[Uruguay]].<ref name="Constanza">{{cite journal|last1=Moreira|first1=Constanza|title=Party systems, political alternation and ideology in the south cone (Argentina, Brazil, Chile and Uruguay)|journal=Revista Uruguaya de Ciencia Política|volume=2|issue=SE|date=2006|url=http://socialsciences.scielo.org/scielo.php?script=sci_arttext&pid=S0797-97892006000200001|access-date=24 January 2018|archive-date=24 January 2018|archive-url=https://web.archive.org/web/20180124195717/http://socialsciences.scielo.org/scielo.php?script=sci_arttext&pid=S0797-97892006000200001|url-status=live}}</ref>

As in other regions, the original rivalry between liberals and conservatives was overtaken by a rivalry between [[center-left]] (often [[social-democratic]]) parties versus [[center-right]] [[liberal conservative]] parties, focusing more in economic differences than in cultural and religious differences as it was common during the liberal versus conservative period. Examples of this include [[National Liberation Party (Costa Rica)|National Liberation Party]] versus [[Social Christian Unity Party]] in [[Costa Rica]], the [[peronista]] [[Justicialist Party]] versus [[Radical Civic Union]] in [[Argentina]], [[Democratic Action (Venezuela)|Democratic Action]] versus [[COPEI]] in [[Venezuela]], the [[Colombian Liberal Party]] versus the [[Colombian Conservative Party]] in Colombia, [[Democratic Revolutionary Party]] versus [[Panameñista Party]] in [[Panama]] and [[Liberal Party of Honduras|Liberal Party]] versus [[National Party of Honduras|National Party]] in [[Honduras]].<ref name="Angell">{{cite journal|last1=Angell|first1=Alan|title=Party Systems in Latin America |journal=Political Quarterly|volume=37|issue=3|pages=309–323|date=July 1966|doi=10.1111/j.1467-923X.1966.tb00224.x}}</ref> After the democratization of Central America following the end of the [[Central American crisis]] in the 1990s former [[far-left]] [[guerrillas]] and former [[right-wing]] authoritarian parties, now in peace, make some similar two-party systems in countries like [[Nicaragua]] between the [[Sandinista National Liberation Front]] and the [[Liberalism in Nicaragua|Liberals]] and in [[El Salvador]] between the [[Farabundo Martí National Liberation Front]] and the [[Nationalist Republican Alliance]].

The traditional two-party dynamic started to break after a while, especially in the early 2000s; alternative parties won elections breaking the traditional two-party systems including [[Rafael Caldera]]'s ([[National Convergence (Venezuela)|National Convergence]]) [[1993 Venezuelan general election|victory]] in [[Venezuela]] in 1993, [[Álvaro Uribe]] ([[Colombia First]]) [[2002 Colombian presidential election|victory]] in 2002, [[Tabaré Vázquez]] ([[Broad Front (Uruguay)|Broad Front]]) [[2004 Uruguayan general election|victory]] in [[Uruguay]] in 2004, [[Fernando Lugo]] ([[Christian Democratic Party (Paraguay)|Christian Democratic Party]]) [[2008 Paraguayan general election|victory]] in [[Paraguay]] in 2008, [[Ricardo Martinelli]] ([[Democratic Change (Panama)|Democratic Change]]) [[2009 Panamanian general election|victory]] in 2009 in [[Panama]], [[Luis Guillermo Solís]] ([[Citizens' Action Party (Costa Rica)|Citizens' Action Party]]) [[2014 Costa Rican general election|victory]] in 2014 in [[Costa Rica]], [[Mauricio Macri]] ([[Republican Proposal]]) [[2015 Argentine general election|victory]] in 2015 in [[Argentina]], [[Nayib Bukele]] ([[Grand Alliance for National Unity]]) [[2019 Salvadoran presidential election|victory]] in 2019 in [[El Salvador]], and [[Gabriel Boric]] ([[Apruebo Dignidad|Approve Dignity]]) [[2021 Chilean general election|victory]] in 2021 in [[Chile]], all of them from non-traditional [[third party (politics)|third parties]] in their respective countries.<ref name="Angell" /> In some countries like Argentina, Chile and Venezuela the political system is now split in two large multi-party alliances or blocs, one on the left and one on the right of the spectrum,<ref name="Constanza" /> such as [[Frente de Todos]] versus [[Juntos por el Cambio]] in Argentina, and the [[Unitary Platform]] versus [[Great Patriotic Pole]] in Venezuela.

=== Brazil ===
{{Main|Political parties in Brazil}}
During the [[Empire of Brazil|imperial period]], since 1840, two great parties with a national base alternated its dominance between legislatures: the [[Liberal Party (Brazil, 1831)|Liberal]] and the [[Conservative Party (Brazil)|Conservative]]. These parties were dissolved in 1889, after the republic was instituted in Brazil, in which the registration of party directories came under the jurisdiction of the states.

[[Brazil]] also had a two-party system for most of [[Brazilian military government|its military dictatorship]] (1964–1985): on October 27, 1965, the Institutional Act 2 decree<ref>{{cite web |title=AIT-02-65 |url=http://www.planalto.gov.br/ccivil_03/ait/ait-02-65.htm |website=www.planalto.gov.br}}</ref> banned all existing parties and conditioned the creation of new parties to the quorum of 1/3 of the then-elected National Congress; resulting in the creation of two parties: a pro-government party, the [[National Renewal Alliance]] (ARENA) and an opposition party, the [[Brazilian Democratic Movement]] (MDB). Despite officially having a bipartisan system, complex electoral mechanisms, nominally neutral, were created to guarantee the prevalence of the ARENA in the [[National Congress of Brazil|National Congress]], making Brazil, in practice, a [[dominant-party system]] in that period. The two parties were dissolved in 1979, when the regime allowed other parties to form.<ref>{{cite web |url=https://www.britannica.com/place/Brazil/Political-parties |title=Brazil – Political parties |last1=Martins |first1=Luciano |last2=Schneider |first2=Ronald Milton |author-link2=Ronald Schneider (historian) |website=[[britannica.com]] |access-date=23 September 2017 |archive-date=24 September 2017 |archive-url=https://web.archive.org/web/20170924002247/https://www.britannica.com/place/Brazil/Political-parties |url-status=live }}</ref>

== Asia ==

=== Lebanon ===
{{Main|Politics of Lebanon}}
The [[Parliament of Lebanon]] is mainly made up of two [[bipartisan]] alliances. Although both alliances are made up of several political parties on both ends of the [[political spectrum]] the two-way political situation has mainly arisen due to strong ideological differences in the electorate.<ref>{{Cite news| url=http://news.bbc.co.uk/1/hi/world/middle_east/6173322.stm| title=The Lebanese crisis explained| date=2007-05-22| access-date=2017-10-24| archive-date=2008-01-23| archive-url=https://web.archive.org/web/20080123104933/http://news.bbc.co.uk/1/hi/world/middle_east/6173322.stm| url-status=live}}</ref> Once again this can mainly be attributed to the [[Plurality voting system|winner takes all]] thesis.

=== South Korea ===
{{Main|Political parties of South Korea}}
[[Politics of South Korea|South Korea]] has a multi-party system<ref>The New York Times, August 21, 2006, [https://www.nytimes.com/2006/08/21/world/asia/21iht-letter.2549074.html?_r=0 Post-Koizumi, dream of a two-party system] {{Webarchive|url=https://web.archive.org/web/20200226042026/https://www.nytimes.com/2006/08/21/world/asia/21iht-letter.2549074.html?_r=0 |date=2020-02-26 }}, Accessed Oct. 18, 2013, quote:  "...This is positive. A two-party system isn't here yet, but it's a kind of dream we have..."</ref> that has sometimes been described as having characteristics of a two-party system.<ref>{{cite news|author= Jung Sang-Geun|title= '그들만의 양당제', 유권자가 정치에 관심을 끊은 이유|publisher= Mediatoday|date= July 10, 2013|url= http://www.mediatoday.co.kr/news/articleView.html?idxno=110739|access-date= 2013-10-18|archive-date= 2013-10-19|archive-url= https://web.archive.org/web/20131019161525/http://www.mediatoday.co.kr/news/articleView.html?idxno=110739|url-status= live}}</ref> Parties will have reconstructions based upon its leader, but the country continues to maintain two major parties. Currently these parties are the [[Liberalism in South Korea|liberal]] [[Democratic Party (South Korea, 2015)|Democratic Party of Korea]] and the [[Conservatism in South Korea|conservative]] [[People Power Party (South Korea)|People Power Party]].

==Comparison with other systems==
{{See also|Top-four primary}}
Two-party systems can be contrasted with:

*[[Multi-party system]]s. In these, the [[effective number of parties]] is greater than two but usually fewer than five; in a two-party system, the effective number of parties is two (according to one analysis, the actual average number of parties varies between 1.7 and 2.1).<ref>{{cite book |url=https://books.google.com/books?id=Hsz3ML3hgUUC&q=%22two+party+system%22+effective+number+of+parties&pg=PA69 |title=Electoral Systems and Party Systems: A Study of Twenty-Seven Democracies ... |via=Google Books |access-date=2012-10-29 |isbn=978-0198273479 |year=1994 |last1=Lijphart |first1=Arend |last2=Aitkin |first2=Don |publisher=Oxford University Press |archive-date=2020-10-02 |archive-url=https://web.archive.org/web/20201002181318/https://books.google.com/books?id=Hsz3ML3hgUUC&pg=PA69&dq=%22two+party+system%22+effective+number+of+parties |url-status=live }}</ref> The parties in a multi-party system can control government separately or as a coalition; in a two-party system, coalition governments rarely form. Nations with multi-party systems include [[Belgium]], [[Brazil]], [[Denmark]], [[Finland]], [[France]], [[Germany]], [[India]], [[Indonesia]], [[Republic of Ireland|Ireland]], [[Israel]], [[Italy]], [[Mexico]], [[Nepal]], the [[Netherlands]], [[New Zealand]], [[Norway]], [[Pakistan]], [[Philippines]], [[Portugal]], [[Ukraine]], [[Suriname]], [[Sweden]] and [[Thailand]].

*[[Dominant-party system]]s are present where a dominant party holds a vast majority for decades and the party institutions may be intertwined with, or hard to distinguish from the major institutions of the state. Unlike in one-party-states, [[civil rights]] and [[freedom of press]] may be preserved. This can occur in countries which are formally democratic (such as the case of the [[People's Action Party]] of [[Singapore]], the [[African National Congress]] of [[South Africa]], the [[Colorado Party (Paraguay)|Colorado Party]] in [[Paraguay]], the [[SWAPO]] in [[Namibia]], and the [[Dominica Labour Party]] in [[Dominica]]) or in countries which are only nominally democratic, where the allowance of the existence of multiple parties is merely a front to give the illusion of a democratic system (such as the case of the [[People's Democratic Party of Tajikistan]] in [[Tajikistan]], the [[New Azerbaijan Party]] in [[Azerbaijan]], the [[Democratic Party of Turkmenistan]] in [[Turkmenistan]], [[United Russia]] in [[Russia]], the [[Union for the Republic (Togo)|Union for the Republic]] in [[Togo]], the [[Democratic Party of Equatorial Guinea]] in [[Equatorial Guinea]], and the [[Cameroon People's Democratic Movement]] in [[Cameroon]]).

*[[One-party state|One-party systems]] happen in nations where no more than one party is codified in law and/or officially recognized, or where alternate parties are restricted (sometimes constitutionally) by or in favor of the dominant party which wields power. Examples are rule by the [[Communist Party of Vietnam]] and [[Communist Party of Cuba]] in the former case, and the [[Chinese Communist Party]] and [[Workers' Party of Korea]] in the latter case.

==Causes==
There are several reasons why, in some systems, two major parties dominate the political landscape. There has been speculation that a two-party system arose in the [[United States]] from early political battling between the federalists and anti-federalists in the first few decades after the ratification of the [[United States Constitution|Constitution]], according to several views.<ref name=SchmidtTextbook/><ref name=twsNovGi11>{{cite news
|author= Michiko Kakutani (book reviewer) American Creation (book by Joseph J. Ellis)
|title= The Timing, Luck and Lust Behind the Forming of That More Perfect Union
|newspaper= The New York Times
|quote= the standoff between the Federalists and their opponents, which led to the modern two-party system
|date= November 27, 2007
|url= https://www.nytimes.com/2007/11/27/books/27kaku.html?pagewanted=print
|access-date= 2010-11-07
|archive-date= 2015-06-05
|archive-url= https://web.archive.org/web/20150605074901/http://www.nytimes.com/2007/11/27/books/27kaku.html?pagewanted=print
|url-status= live
}}</ref> In addition, there has been more speculation that the winner-takes-all electoral system as well as particular state and federal laws regarding voting procedures helped to cause a two-party system.<ref name=SchmidtTextbook>{{cite news
|last1= Schmidt |first1=Steffen W.
|author-link1= Steffen Schmidt
|last2= Shelley |first2=Mack C.
|last3=Bardes |first3=Barbara A.
|title= American Government and Politics Today 2008–2009
|publisher= Wadsworth Publishing Company
|year= 2008
|isbn= 9780495503224
|url= https://books.google.com/books?id=QJrSm1q-gbQC&q=%22two-party+system%22+United+States+historical+foundations&pg=PA173
|access-date= 2010-11-22
|archive-date= 2020-02-29
|archive-url= https://web.archive.org/web/20200229003310/https://books.google.com/books?id=QJrSm1q-gbQC&pg=PA173&dq=%22two-party+system%22+United+States+historical+foundations#v=onepage&q=%22two-party%20system%22%20United%20States%20historical%20foundations&f=false
|url-status= live
}}</ref>
[[File:Two Party Ballot In New Jersey.jpg|thumb|right|alt=Voting ballot.|In a two-party system, voters have mostly two options; in this sample ballot for an election in [[Summit, New Jersey]], voters can choose between a Republican or Democrat, but there are no third party candidates.]]

[[File:FMSTAN & SPIDER Global meeting in Austrian Foreign Ministries in Vienna (49120446508) (cropped).jpg|thumb|right|Economist [[Jeffrey D. Sachs]]]]
Political scientists such as [[Maurice Duverger]]<ref name=GeorgeEdwards>{{Cite book
| last = Edwards III
| first = George C.
| title = Why the Electoral College is Bad for America
| publisher = Yale University Press
| edition = Second
| year = 2011
| location = New Haven and London
| pages = 176–77
| isbn =978-0-300-16649-1}}</ref> and [[William H. Riker]] claim that there are strong correlations between voting rules and type of party system. [[Jeffrey D. Sachs]] agreed that there was a link between voting arrangements and the effective number of parties. Sachs explained how the [[first-past-the-post]] voting arrangement tended to promote a two-party system:

{{Quote|The main reason for America's majoritarian character is the electoral system for Congress. Members of Congress are elected in single-member districts according to the "first-past-the-post" (FPTP) principle, meaning that the candidate with the plurality of votes is the winner of the congressional seat. The losing party or parties win no representation at all. The first-past-the-post election tends to produce a small number of major parties, perhaps just two, a principle known in political science as [[Duverger's Law]]. Smaller parties are trampled in first-past-the-post elections.|Sachs, ''The Price of Civilization'', 2011<ref name=twsM18xxuy>{{cite book
| last = Sachs
| first = Jeffrey
| title = The Price of Civilization
| publisher = Random House
| year = 2011
| location = New York
| page = 107
| isbn = 978-1-4000-6841-8}}</ref>}}

Consider a system in which voters can vote for any candidate from any one of many parties. Suppose further that if a party gets 15% of votes, then that party will win 15% of the seats in the legislature. This is termed ''proportional representation'' or more accurately as ''party-proportional representation''. Political scientists speculate that proportional representation leads logically to multi-party systems, since it allows new parties to build a niche in the legislature:

{{Quote|Because even a minor party may still obtain at least a few seats in the legislature, smaller parties have a greater incentive to organize under such electoral systems than they do in the United States.|Schmidt, Shelley, Bardes (2008)<ref name=SchmidtTextbook/>}}

In contrast, a voting system that allows only a single winner for each possible legislative seat is sometimes termed a [[single-winner voting system]] and is usually described under the heading of a ''winner-takes-all'' arrangement in the case of a [[plurality voting system]]. Each voter can cast a single vote for any candidate within any given legislative district, but the candidate with the most votes wins the seat, although variants, such as requiring a majority, are sometimes used. What happens is that in a general election, a party that consistently comes in third in every district is unlikely to win any legislative seats even if there is a significant proportion of the electorate favoring its positions. This arrangement strongly favors large and well-organized political parties that are able to appeal to voters in many districts and hence win many seats, and discourages smaller or regional parties. Politically oriented people consider their only realistic way to capture political power is to run under the auspices of the two dominant parties,<ref name=SchmidtTextbook/> and legislators from both dominant parties have an incentive not to reform the system as it eliminates potential choices and multiple competing policy options, meaning that they do not necessarily need to adopt positions favorable to voters, but only need to be seen as marginally less unfavorable than the only other option to gain votes.

In the U.S., forty-eight states have a standard ''winner-takes-all'' electoral system for amassing presidential votes in the [[Electoral College (United States)|Electoral College]] system.<ref name=twsNovGf1>{{cite magazine
|first= Kristina |last=Dell
|title= The Electoral College Explained
|magazine=[[Time (magazine)|Time]]
|quote= Forty-eight states have the standard "winner-takes-all" electoral system: whichever presidential ticket amasses the most popular votes in a state wins all the electors of that state.
|date= Nov 1, 2004
|url= http://www.time.com/time/election2004/article/0,18471,749496,00.html
|access-date= 2010-11-07
|archive-date= 2010-07-10
|archive-url= https://web.archive.org/web/20100710125857/http://www.time.com/time/election2004/article/0,18471,749496,00.html
|url-status= dead
}}</ref> The ''winner-takes-all'' principle applies in presidential elections, since if a presidential candidate gets the most votes in any particular state, ''all'' of the [[electoral votes]] from that state are awarded. In all but two states, [[Maine]] and [[Nebraska]], the presidential candidate winning a plurality of votes wins all of the electoral votes, a practice called the '''unit rule'''.<ref name=SchmidtTextbook/>

Duverger concluded that "plurality election single-ballot procedures are likely to produce two-party systems, whereas proportional representation and runoff designs encourage multipartyism."<ref name=GeorgeEdwards/> He suggested there were two reasons why ''winner-takes-all'' systems leads to a two-party system. First, the weaker parties are pressured to form an alliance, sometimes called a ''fusion'', to try to become big enough to challenge a large dominant party and, in so doing, gain political clout in the legislature. Second, voters learn, over time, not to vote for candidates outside of one of the two large parties since their votes for third party candidates are usually ineffectual.<ref name=SchmidtTextbook/> As a result, weaker parties are eliminated by voters over time. Duverger pointed to statistics and tactics to suggest that voters tended to gravitate towards one of the two main parties, a phenomenon which he called ''polarization'', and tend to shun third parties.<ref name=EricBlack/> For example, some analysts suggest that the [[Electoral College (United States)|Electoral College]] system in the [[United States]], by favoring a system of winner-takes-all in presidential elections, is a structural choice favoring only two major parties.<ref name=twsNovGf2>{{cite magazine
|first= Kristina |last=Dell
|title= The Electoral College Explained
|magazine=[[Time (magazine)|Time]]
|date= November 1, 2004
|url= http://www.time.com/time/election2004/article/0,18471,749496,00.html
|access-date= 2010-11-07
|archive-date= 2010-07-10
|archive-url= https://web.archive.org/web/20100710125857/http://www.time.com/time/election2004/article/0,18471,749496,00.html
|url-status= dead
}}</ref>

Gary Cox suggested that America's two-party system was highly related with economic prosperity in the country:

{{Quote|The bounty of the American economy, the fluidity of American society, the remarkable unity of the American people, and, most important, the success of the American experiment have all mitigated against the emergence of large dissenting groups that would seek satisfaction of their special needs through the formation of political parties.|Cox, according to George Edwards<ref name=GeorgeEdwards/>}}

However, as of 2022, United States' [[Gini coefficient]] (which measures income inequality) ranks near the worst of [[OECD]] countries and in the bottom half of all countries, while the country ranks outside the top five countries in terms of [[GDP per capita]].

An effort in 2012 by centrist groups to promote [[ballot access]] by third-party candidates called [[Americans Elect]] spent $15 million to get ballot access but failed to elect any candidates.<ref>{{cite magazine |first=Michael |last=Crowley |date=May 21, 2012 |magazine=[[Time (magazine)|Time]] |url=http://www.time.com/time/magazine/article/0,9171,2114426-1,00.html |title=Indie Block: Why has a third-party presidential effort sputtered? |archive-url=https://web.archive.org/web/20120516234452/http://www.time.com/time/magazine/article/0,9171,2114426-1,00.html |archive-date=May 16, 2012 |access-date=August 11, 2013 |url-status=dead |quote=...and another $15 million has gone toward its most valuable asset: ballot access. Americans Elect has secured a ballot line in 26 states..}}</ref> The lack of choice in a two-party model in politics has often been compared to the variety of choices in the marketplace.

{{Quote|Politics has lagged our social and business evolution&nbsp;... There are 30 brands of Pringles in our local grocery store. How is it that Americans have so much selection for potato chips and only two brands{{snd}}and not very good ones{{snd}}for political parties?|Scott Ehredt of the Centrist Alliance<ref name=Cillizza>{{cite news |first=Chris |last=Cillizza |date=July 24, 2011 |newspaper=The Washington Post |url=https://www.washingtonpost.com/politics/voters-renewed-anger-at-washington-spurs-formation-of-third-party-advocate-groups/2011/07/24/gIQAts3KXI_story.html |title=Voters' renewed anger at Washington spurs formation of third-party advocate groups |archive-url=https://web.archive.org/web/20180621015857/https://www.washingtonpost.com/politics/voters-renewed-anger-at-washington-spurs-formation-of-third-party-advocate-groups/2011/07/24/gIQAts3KXI_story.html |archive-date=2018-06-21 |access-date=August 11, 2013}}</ref>}}

==Third parties==
{{Main|Third party (politics)|Third party (United States)}}
[[File:Two party system diagram.png|thumb|upright=1.6|According to one view, the winner-takes-all system discourages voters from choosing third party or independent candidates, and over time the process becomes entrenched so that only two major parties become viable.]]
Third parties, meaning a party other than one of the two dominant parties, are possible in two-party systems, but they are often unlikely to exert much influence by gaining control of legislatures or by winning elections.<ref name=SchmidtTextbook/> While there are occasional opinions in the media expressed about the possibility of third parties emerging in the United States, for example, political insiders such as the 1980 presidential candidate John Anderson think the chances of one appearing in the early twenty-first century is remote.<ref name="twsDecG44fwee">{{cite magazine
|author= Ryan Lizza
|title= But Is a Third Party Possible?
|magazine= New York Magazine
|date= Apr 16, 2006
|url= https://nymag.com/news/politics/16743/
|access-date= 2010-12-07
|archive-date= 2011-09-26
|archive-url= https://web.archive.org/web/20110926085019/http://nymag.com/news/politics/16743/
|url-status= live
}}</ref> A report in ''[[The Guardian]]'' suggested that American politics has been "stuck in a two-way fight between [[Republican Party (United States)|Republicans]] and [[Democratic Party (United States)|Democrats]]" since the [[American Civil War|Civil War]], and that third-party runs had little meaningful success.<ref name=twsJanQ>{{cite news
|author= Paul Harris
|title= 'America is better than this': paralysis at the top leaves voters desperate for change
|newspaper= The Guardian
|date= 19 November 2011
|url= https://www.theguardian.com/world/2011/nov/20/paralysis-in-us-politics-extremism
|access-date= 2012-01-17
|archive-date= 2013-10-01
|archive-url= https://web.archive.org/web/20131001065314/http://www.theguardian.com/world/2011/nov/20/paralysis-in-us-politics-extremism
|url-status= live
}}</ref>

Third parties in a two-party system can be:
* Built around a particular ideology or interest group
* Split off from one of the major parties or
* Focused on a [[charisma|charismatic individual]].<ref name="twsDecG44fwee"/>
[[File:U.S. party affiliation.svg|thumb|Party affiliation in the United States according to a 2004 study: Democratic with 72 million, Republican with 55 million and third parties collectively with 42 million registered citizens<ref>{{cite web |last=Neuharth |first=Al |author-link=Al Neuharth |url=https://usatoday30.usatoday.com/news/opinion/columnist/neuharth/2004-01-22-neuharth_x.htm |title=Why politics is fun from catbirds' seats |date=22 January 2004 |access-date=3 February 2023 |publisher=[[USA Today]]}}</ref>]]

When third parties are built around an ideology which is at odds with the majority mindset, many members belong to such a party not for the purpose of expecting electoral success but rather for personal or psychological reasons.<ref name=SchmidtTextbook/> In the U.S., third parties include older ones such as the [[Libertarian Party (United States)|Libertarian Party]] and the [[Green Party (United States)|Green Party]] and newer ones such as the [[United States Pirate Party|Pirate Party]].<ref name=SchmidtTextbook/><ref name=twsMarZ2la>{{cite news
|author= Jack Schofield
|title= Sweden's Pirate Party wins EU seat (updated)
|newspaper= The Guardian
|quote= The Pirate Party ... wants to legalise internet file-sharing and protect people's privacy on the net ... There *IS* a UK Pirate Party ... and there's a US ... one, and one in a few dozen others."
|date= 8 June 2009
|url= https://www.theguardian.com/technology/blog/2009/jun/08/elections-pirate-party-sweden
|access-date= 2011-03-28
|archive-date= 2014-02-13
|archive-url= https://web.archive.org/web/20140213215401/http://www.theguardian.com/technology/blog/2009/jun/08/elections-pirate-party-sweden
|url-status= live
}}</ref> Many believe that third parties do not affect American politics by winning elections, but they can act as "spoilers" by taking votes from one of the two major parties.<ref name=SchmidtTextbook/> They act like barometers of change in the political mood since they push the major parties to consider their demands.<ref name=SchmidtTextbook/> An analysis in ''[[New York Magazine]]'' by Ryan Lizza in 2006 suggested that third parties arose from time to time in the nineteenth century around single-issue movements such as abolition, women's suffrage, and the direct election of senators, but were less prominent in the twentieth century.<ref name=twsDecG44aa>{{cite magazine
|author= Ryan Lizza
|title= But Is a Third Party Possible?
|magazine= New York Magazine
|quote= In the nineteenth century, third parties were single-issue creatures that grew up around great causes that the major parties were ignoring. Abolition, women's suffrage, and the direct election of senators all started as third-party movements.
|date= Apr 16, 2006
|url= https://nymag.com/news/politics/16743/
|access-date= 2010-12-07
|archive-date= 2011-09-26
|archive-url= https://web.archive.org/web/20110926085019/http://nymag.com/news/politics/16743/
|url-status= live
}}</ref> With a [[Electoral fusion in the United States|fusion]] nomination, a candidate can appear under two separate labels, allowing voters to show support for a candidate and a party.<ref>{{Cite web |last=Monitor |first=Special to the New Jersey |date=2024-12-09 |title=Fusion voting would encourage coalitions, decrease polarization • New Jersey Monitor |url=https://newjerseymonitor.com/2024/12/09/fusion-voting-would-encourage-coalitions-decrease-polarization/ |access-date=2025-03-01 |website=New Jersey Monitor |language=en-US}}</ref>

A so-called ''third party'' in the [[United Kingdom]] were historically the [[Liberal Democrats (UK)|Liberal Democrats]], prior to the [[Scottish National Party]] taking its place from the [[2015 United Kingdom general election|2015 election]] until the [[2024 United Kingdom general election|2024 election]] by number of the House of Common seats. In the [[2010 United Kingdom general election|2010 election]], the Liberal Democrats received 23% of the votes but only 9% of the seats in the [[House of Commons of the United Kingdom|House of Commons]]. While electoral results do not necessarily translate into legislative seats, the Liberal Democrats can exert influence if there is a situation such as a [[hung parliament]]. In this instance, neither of the two main parties (at present, the [[Conservative Party (UK)|Conservative Party]] and the [[Labour Party (UK)|Labour Party]]) have sufficient authority to run the government. Accordingly, the Liberal Democrats can in theory exert tremendous influence in such a situation since they can ally with one of the two main parties to form a coalition. This happened in the [[Cameron–Clegg coalition|coalition government of 2010]]. The two party system in the United Kingdom allows for other parties to exist, although the main two parties tend to dominate politics (for example, the aforementioned coalition government was the first multi-party government since the government of Winston Churchill in the early- to mid-1940s); in this arrangement, other parties are not excluded and can win seats in Parliament. In contrast, the two party system in the United States has been described as a duopoly or an enforced two-party system, such that politics is almost entirely dominated by either the Republicans or Democrats, and third parties rarely win seats in [[United States Congress|Congress]],<ref>Gillespie, J. D. (2012). Challengers to Duopoly: Why Third Parties Matter in American Two-party Politics. University of South Carolina Press.</ref> state legislatures, or even at the local level.

==Advantages==
Some historians have suggested that two-party systems promote centrism and encourage political parties to find common positions which appeal to wide swaths of the electorate. It can lead to political stability,<ref name=Regis/>{{failed verification|date=March 2017}} which leads, in turn, to economic growth. Historian [[Patrick Allitt]] of the [[Teaching Company]] suggested that it is difficult to overestimate the long-term economic benefits of political stability. Sometimes two-party systems have been seen as preferable to multi-party systems because they are simpler to govern, with less fractiousness and greater harmony, since it discourages radical minor parties,<ref name=Regis/> while multi-party systems can sometimes lead to [[hung parliament]]s.<ref name=twsNovGh33>{{cite news
|title= What mean will we regress to?
|newspaper= The Economist
|quote= Certainly, there have been a whole lot of hung parliaments and slow-forming coalitions around the world lately. (Canada, Australia, Britain, the Netherlands, Iraq...)
|date= Oct 5, 2010
|url= https://www.economist.com/blogs/democracyinamerica/2010/10/election_dynamics
|access-date= 2010-11-07
|archive-date= 2010-11-09
|archive-url= https://web.archive.org/web/20101109201358/http://www.economist.com/blogs/democracyinamerica/2010/10/election_dynamics
|url-status= live
}}</ref> [[Politics in Italy|Italy]], with a multi-party system, has had years of divisive politics since 2000, although analyst Silvia Aloisi suggested in 2008 that the nation may be moving closer to a two-party arrangement,<ref name=twsNovGc>{{cite news
|author= Silvia Aloisi
|title= Election pushes Italy towards two-party system
|work= Reuters
|quote= Italy's next parliament will have far fewer parties than the previous assembly, pushing the country closer to the two-party system that many commentators say is the only way to end years of political instability. ...
|date= Apr 15, 2008
|url= https://www.reuters.com/article/idUSL1580537620080415
|access-date= 2010-11-07
|archive-date= 2020-10-02
|archive-url= https://web.archive.org/web/20201002181318/https://www.reuters.com/article/idUSL1580537620080415
|url-status= live
}}</ref> although this no longer seemed the case by the 2010s, which saw the rise of the [[Five Star Movement]] and [[Lega (political party)|Lega]]. The two-party system has generally been identified as simpler since there are fewer voting choices.<ref name=Regis/>

==Disadvantages==
Two-party systems have been criticized for downplaying alternative views,<ref name=Regis/><ref name=Boundless/> being less competitive,<ref name=Cato/> failing the [[median voter theorem]], encouraging voter apathy since there is a perception of fewer choices,<ref name=Regis/> and putting a damper on debate<ref name=Boundless/> within a nation. In a proportional representation system, lesser parties can moderate policy since they are not usually eliminated from government.<ref name=Regis/> One analyst suggested the two-party approach may not promote inter-party compromise but may encourage partisanship.<ref name=Boundless/> In ''The Tyranny of the Two-party system'', Lisa Jane Disch criticizes two-party systems for failing to provide enough options since only two choices are permitted on the ballot. She wrote:

{{Quote|Herein lies the central tension of the two–party doctrine. It identifies [[popular sovereignty]] with choice, and then limits choice to one party or the other. If there is any truth to Schattschneider's analogy between elections and markets, America's faith in the two–party system begs the following question: Why do voters accept as the ultimate in political freedom a binary option they would surely protest as consumers? ... This is the tyranny of the two–party system, the construct that persuades United States [[Citizenship in the United States|citizens]] to accept two–party contests as a ''condition'' of electoral democracy.|Lisa Jane Disch, 2002<ref name=twsOctNfasfgg>{{cite book
|author= Lisa Jane Disch
|title= The tyranny of the two-party system
|publisher= Columbia University Press
|year= 2002
|isbn= 978-0231110358
|url= https://books.google.com/books?id=Cm5a9X0hpyUC&q=hicks
|access-date= 2010-10-22
|archive-date= 2011-12-26
|archive-url= https://web.archive.org/web/20111226094322/http://books.google.com/books?id=Cm5a9X0hpyUC&printsec=frontcover&dq=two+party+system#v=onepage&q=hicks&f=false
|url-status= live
}}</ref>}}

There have been arguments that the winner-take-all mechanism discourages independent or third-party candidates from running for office or promulgating their views.<ref name=Cato/><ref name=twsNovGf3>{{cite magazine
|author= Kristina dell
|title= The Electoral College Explained
|magazine= Time Magazine
|quote= Some argue that the winner-take-all mechanism in 48 states discourages independent or third party candidates from running because it would be difficult for them to get many electoral votes.
|date= Nov 1, 2004
|url= http://www.time.com/time/election2004/article/0,18471,749496,00.html
|access-date= 2010-11-07
|archive-date= 2010-07-10
|archive-url= https://web.archive.org/web/20100710125857/http://www.time.com/time/election2004/article/0,18471,749496,00.html
|url-status= dead
}}</ref> [[Ross Perot]]'s former campaign manager wrote that the problem with having only two parties is that the nation loses "the ability for things to bubble up from the body politic and give voice to things that aren't being voiced by the major parties."<ref name="twsDecG44fwee"/> One analyst suggested that parliamentary systems, which typically are multi-party in nature, lead to a better "centralization of policy expertise" in government.<ref name=twsNovGg45>{{cite news
|title= The advantages of parliamentarianism
|newspaper= The Economist
|date= Jan 21, 2010
|url= https://www.economist.com/blogs/democracyinamerica/2010/01/more_advantages_parliamentarianism_let_politicians_be_politicians
|access-date= 2010-11-07
|archive-date= 2010-11-25
|archive-url= https://web.archive.org/web/20101125020447/http://www.economist.com/blogs/democracyinamerica/2010/01/more_advantages_parliamentarianism_let_politicians_be_politicians
|url-status= live
}}</ref> Multi-party governments permit wider and more diverse viewpoints in government, and encourage dominant parties to make deals with weaker parties to form winning coalitions.<ref name=twsNovGi22>{{cite news
|author= Chris Weigant
|title= Exceptional Democracy
|work= Huffington Post
|quote= And, as a result, more parties are represented in their parliament after the elections. The Italian Parliament, for instance, recently had more than 70 parties represented. ... These deals are cut with the smaller parties by offering them the chance to fill high government offices...
|date= April 7, 2010
|url= https://www.huffingtonpost.com/chris-weigant/exceptional-democracy_b_529411.html
|access-date= 2010-11-07
|archive-date= 2010-04-13
|archive-url= https://web.archive.org/web/20100413195116/http://www.huffingtonpost.com/chris-weigant/exceptional-democracy_b_529411.html
|url-status= live
}}</ref> Analyst Chris Weigant of ''[[the Huffington Post]]'' wrote that "the parliamentary system is inherently much more open to minority parties getting much better representation than third parties do in the American system".<ref name=twsNovGi22/> After an election in which the party changes, there can be a "polar shift in policy-making" when voters react to changes.<ref name=Regis/>

Political analyst A. G. Roderick, writing in his book ''Two Tyrants'', argued that the two American parties (the Republican Party and the Democratic Party) were highly unpopular (as of 2015), are not part of the political framework of state governments, and do not represent the 47% of the electorate who identify themselves as "independents".<ref name=WPR/> He makes a case that the [[POTUS|American president]] should be elected on a non-partisan basis,<ref name=WPR>Wisconsin Public Radio, [http://www.wpr.org/listen/767011 Two Tyrants] {{Webarchive|url=https://web.archive.org/web/20160506221352/http://www.wpr.org/listen/767011 |date=2016-05-06 }} interview by Kathleen Dunn with author A.G. Roderick</ref><ref name=twoTyrants>{{cite book
|title= Two Tyrants
|author= A.G. Roderick
|publisher= City of Gold Publishing
|year= 2014
|isbn= 978-0990889205
|url= https://www.goodreads.com/book/show/23411553-two-tyrants
|access-date= 2016-04-23
|archive-date= 2020-10-02
|archive-url= https://web.archive.org/web/20201002181323/https://www.goodreads.com/book/show/23411553-two-tyrants
|url-status= live
}}</ref><ref name="twsWNYCRadio">{{cite web
| date= July 27, 2015
| publisher= WNYC Public Radio
| url= http://www.wnyc.org/story/what-causes-two-party-monopoly-politics/
| title= Republicans and Democrats: America's Two Tyrants?
| access-date= April 23, 2016
| quote= ...only about eight percent of Americans feel confident in our partisan Congress ... 47 percent of Americans ... identify as independents. ...
| archive-date= August 7, 2016
| archive-url= https://web.archive.org/web/20160807191249/http://www.wnyc.org/story/what-causes-two-party-monopoly-politics/
| url-status= live
}}</ref> and asserts that both political parties are "cut from the same cloth of corruption and corporate influence."<ref name="twsHonoMag1">{{cite magazine
| author= Loren Moreno
| date= June 15, 2015
| magazine= Honolulu Magazine
| url= http://www.honolulumagazine.com/Honolulu-Magazine/June-2015/15-Hawaii-Books-to-Read-This-Summer/index.php?cparticle=4
| title= Two Tyrants
| access-date= April 23, 2016
| quote= ... since both parties are cut from the same cloth of corruption and corporate influence, the American populace is left in a "crisis of creativity," ...
| archive-date= May 8, 2016
| archive-url= https://web.archive.org/web/20160508084827/http://www.honolulumagazine.com/Honolulu-Magazine/June-2015/15-Hawaii-Books-to-Read-This-Summer/index.php?cparticle=4
| url-status= live
}}</ref>

Others have accused two party systems of encouraging an environment which stifles individual thought processes and analysis. In a two party system, knowledge about political leaning facilitates assumptions to be made about an individual's opinions on a wide variety of topics (e.g. [[abortion]], [[Tax|taxes]], the [[space program]], a [[Pandemic|viral pandemic]], [[human sexuality]], the [[Environmental issues|environment]], [[War|warfare]], opinions on police, etc.) which are not necessarily connected.<blockquote>"The more destructive problem is the way this skews the discussion of the issues facing the nation. The media – meaning news sources from [[Fox News]] to the [[The New York Times|''New York Times'']] and everything in between – seem largely incapable of dealing with any issue outside of the liberal versus conservative paradigm. Whether it's dealing with [[Islamic State|ISIS]], the [[United States debt ceiling|debt ceiling]], or [[climate change]], the media frames every issue as a simple debate between the Democratic and the Republican positions. This creates the ludicrous idea that every public policy problem has two, and only two, approaches. That's nonsense. Certainly some problems have only two resolutions, some have only one, but most have a range of possible solutions. But the "national" debate presents every issue as a simplistic duality, which trivializes everything."

—Michael Coblenz, 2016<ref>{{Cite web |url=https://thehill.com/blogs/congress-blog/politics/267222-the-two-party-system-is-destroying-america |title=The two-party system is destroying America |work=The Hill |date=January 28, 2016 |access-date=2020-06-22 |archive-date=2020-06-22 |archive-url=https://web.archive.org/web/20200622180212/https://thehill.com/blogs/congress-blog/politics/267222-the-two-party-system-is-destroying-america |url-status=live |last1=Coblenz |first1=Michael }}</ref></blockquote>

==History==
===British parties===
{{Main|Tories (British political party)|Whigs (British political party)}}
[[File:William III Landing at Brixham, Torbay, 5 November 1688.jpg|thumb|Equestrian portrait of William III by [[Jan Wyck]], commemorating the landing at Brixham, Torbay, 5 November 1688]]
The two-party system, in the sense of the looser definition, where two parties dominate politics but in which third parties can elect members and gain some representation in the legislature, can be traced to the development of political parties in the [[United Kingdom]]. There was a division in [[Politics of England|English politics]] at the time of the [[English Civil War|Civil War]] and [[Glorious Revolution]] in the late 17th century.<ref>J. R. Jones, ''The First Whigs. The Politics of the Exclusion Crisis. 1678–1683'' (Oxford University Press, 1961), p. 4.</ref> The [[Whigs (British political party)|Whigs]] supported [[Protestant]] [[constitutional monarchy]] against [[Absolute Monarchy|absolute rule]] and the [[Tory (British political party)|Tories]], originating in the [[Royalist]] (or "[[Cavalier]]") faction of the [[English Civil War]], were conservative royalist supporters of a strong monarchy as a counterbalance to the [[Republicanism in the United Kingdom|republican]] tendencies of [[Parliament]].<ref>Harris, Tim ''Restoration:Charles II and His Kingdoms 1660–1685'' Allen Lane (2005) p. 241</ref> In the following century, the Whig party's support base widened to include emerging industrial interests and wealthy merchants.

The basic matters of principle that defined the struggle between the two factions, were concerning the nature of [[constitutional monarchy]], the desirability of a Catholic king, the extension of [[religious toleration]] to [[Nonconformist (Protestantism)|nonconformist]] Protestants, and other issues that had been put on the liberal agenda through the political concepts propounded by [[John Locke]],<ref>Richard Ashcraft and M. M. Goldsmith, "Locke, Revolution Principles, and the Formation of Whig Ideology", ''Historical Journal'', Dec 1983, Vol. 26 Issue 4, pp. 773–800</ref> [[Algernon Sidney]] and others.<ref>Melinda S. Zook, "The Restoration Remembered: The First Whigs and the Making of their History", ''Seventeenth Century'', Autumn 2002, Vol. 17 Issue 2, pp. 213–34</ref>

Vigorous struggle between the two factions characterised the period from the [[Glorious Revolution]] to the 1715 [[Hanoverian succession]], over the legacy of the overthrow of the [[Stuart dynasty]] and the nature of the new constitutional state. This proto two-party system fell into relative abeyance after the accession to the throne of [[George I of Great Britain|George I]] and the consequent period of [[Whig supremacy]] under [[Robert Walpole]], during which the Tories were systematically purged from high positions in government. Although the Tories were dismissed from office for 50 years, they retained a measure of party cohesion under [[Sir William Wyndham, 3rd Baronet|William Wyndham]] and acted as a united, though unavailing, opposition to Whig corruption and scandals. At times they cooperated with the "Opposition Whigs", Whigs who were in opposition to the Whig government. The ideological gap between the Tories and the Opposition Whigs prevented them from coalescing as a single party.

===British emergence===
The old Whig leadership dissolved in the 1760s into a decade of factional chaos with distinct "[[Grenvillite]]", "[[Bedfordite]]", "[[Rockingham Whigs|Rockinghamite]]", and "[[William Pitt, 1st Earl of Chatham|Chathamite]]" factions successively in power, and all referring to themselves as "Whigs". Out of this chaos, the first distinctive parties emerged. The first such party was the [[Rockingham Whigs]]<ref>{{cite book|url=https://books.google.com/books?id=UH0HNqRBsmMC|title=The Transatlantic Persuasion: The Liberal-Democratic Mind in the Age of Gladstone|author=Robert Lloyd Kelley|year=1990|publisher=Transaction Publishers|page=83|isbn=978-1412840293|access-date=2020-08-29|archive-date=2020-08-19|archive-url=https://web.archive.org/web/20200819235807/https://books.google.com/books?id=UH0HNqRBsmMC|url-status=live}}</ref> under the leadership of [[Charles Watson-Wentworth, 2nd Marquess of Rockingham|Charles Watson-Wentworth]] and the intellectual guidance of the [[political philosophy|political philosopher]] [[Edmund Burke]]. Burke laid out a philosophy that described the basic framework of the political party as "a body of men united for promoting by their joint endeavours the national interest, upon some particular principle in which they are all agreed". As opposed to the instability of the earlier factions, which were often tied to a particular leader and could disintegrate if removed from power, the two party system was centred on a set of core principles held by both sides and that allowed the party out of power to remain as the [[Loyal Opposition]] to the governing party.<ref>{{cite web|url=http://www.jessenorman.com/2013/09/conhome-op-ed-the-usa-radical-conservatism-and-edmund-burke.html|title=ConHome op-ed: the USA, Radical Conservatism and Edmund Burke|access-date=2013-10-19|archive-date=2013-10-20|archive-url=https://web.archive.org/web/20131020123727/http://www.jessenorman.com/2013/09/conhome-op-ed-the-usa-radical-conservatism-and-edmund-burke.html|url-status=live}}</ref>

[[File:A-Block-for-the-Wigs-Gillray.jpeg|thumb|upright=1.35|In ''A Block for the Wigs'' (1783), [[James Gillray]] caricatured [[Charles James Fox|Fox]]'s return to power in a [[Fox–North coalition|coalition]] with [[Frederick North, Lord North|North]]. George III is the blockhead in the center.]]
A genuine two-party system began to emerge,<ref>{{cite book|url=https://books.google.com/books?isbn=0841958270|title=The Emergence of the British Two-Party System, 1760–1832|author=Frank O'Gorman|year=1982|publisher=Holmes & Meier Publishers, Incorporated}}</ref> with the accession to power of [[William Pitt the Younger]] in 1783 leading the new Tories, against a reconstituted "Whig" party led by the [[radicalism (politics)|radical politician]] [[Charles James Fox]].<ref>{{cite web|url=http://www.zum.de/whkmla/sp/0809/minho/gangster1.html|title=The History of Political Parties in England (1678–1914)|access-date=2013-10-19|archive-date=2013-10-20|archive-url=https://web.archive.org/web/20131020144152/http://www.zum.de/whkmla/sp/0809/minho/gangster1.html|url-status=live}}</ref><ref>Parliamentary History, xxiv, 213, 222, cited in Foord, ''His Majesty's Opposition'', 1714–1830, p. 441</ref><ref>Ellen Wilson and Peter Reill, ''Encyclopedia of the Enlightenment'' (2004) p. 298</ref>

The two-party system matured in the early 19th century [[Reform Act 1832|era of political reform]], when the franchise was widened and politics entered into the basic divide between conservatism and liberalism that has fundamentally endured up to the present. The modern [[Conservative Party (UK)|Conservative Party]] was created out of the [[British Tory Party#Pittites|"Pittite" Tories]] by [[Robert Peel]], who issued the [[Tamworth Manifesto]] in 1834 which set out the basic principles of [[Conservatism]] – the necessity in specific cases of reform in order to survive, but an opposition to unnecessary change, that could lead to "a perpetual vortex of agitation". Meanwhile, the Whigs, along with [[free trade]] Tory followers of [[Robert Peel]], and independent [[Radicals (UK)|Radicals]], formed the [[Liberal Party (UK)|Liberal Party]] under [[Henry John Temple, 3rd Viscount Palmerston|Lord Palmerston]] in 1859, and transformed into a party of the growing urban middle-class, under the long leadership of [[William Ewart Gladstone]]. The two party system had come of age at the time of Gladstone and his Conservative rival [[Benjamin Disraeli]] after the [[Reform Act 1867]].<ref>{{cite book|url=https://books.google.com/books?id=UiNAZmRaYrcC|title=Gladstone and Disraeli|author=Stephen J. Lee|year=2005|publisher=Routledge|page=146|isbn=978-1134349272|access-date=2020-08-29|archive-date=2020-10-02|archive-url=https://web.archive.org/web/20201002181318/https://books.google.com/books?id=UiNAZmRaYrcC|url-status=live}}</ref>

===American===
Although the [[Founding Fathers of the United States]] did not originally intend for American politics to be partisan,<ref>{{citation |title=Washington's Farewell Address |title-link=s:Washington's Farewell Address |url=}}</ref> early political controversies in the 1790s saw the emergence of a two-party political system, the [[Federalist Party (United States)|Federalist Party]] and the [[Democratic-Republican Party (United States)|Democratic-Republican Party]], centred on the differing views on federal government powers of [[United States Secretary of the Treasury|Secretary of the Treasury]] [[Alexander Hamilton]] and [[James Madison]].<ref>Richard Hofstadter, ''The Idea of a Party System: The Rise of Legitimate Opposition in the United States, 1780–1840'' (1970)</ref><ref>William Nisbet Chambers, ed. ''The First Party System'' (1972)</ref> A consensus on these issues ended party politics in 1816 for a decade, a period commonly known as the [[Era of Good Feelings]].<ref>Stephen Minicucci, "[http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=275165&fulltextType=RA&fileId=S0898588X04000094 Internal Improvements and the Union, 1790–1860]", ''Studies in American Political Development'' (2004), 18: pp. 160–85, (2004), Cambridge University Press, {{doi|10.1017/S0898588X04000094}}. {{Webarchive|url=https://web.archive.org/web/20160822070745/http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=275165&fulltextType=RA&fileId=S0898588X04000094 |date=2016-08-22 }}.</ref>

Partisan politics revived in 1829 with the split of the Democratic-Republican Party into the [[Jacksonian Democracy|Jacksonian Democrats]] led by [[Andrew Jackson]], and the [[Whig Party (United States)|Whig Party]], led by [[Henry Clay]]. The former evolved into the modern [[Democratic Party (United States)|Democratic Party]] and the latter was replaced with the [[History of United States Republican Party|Republican Party]] as one of the two main parties in the 1850s.

==See also==
* [[Duverger's law]]
* [[False dichotomy]]
* [[Multi-party system]]
* [[Dominant-party system]]
* [[One-party state]]
* [[Political organisation]]
* [[Uniparty]]

==Notes==
{{Notelist}}

==References==
{{Reflist}}

==External links==
{{Sister project links|wikt=two-party system|c=no|n=no|q=Two-party system|s=no|b=no|v=no|d=Q233008}}
* [[Patrick Dunleavy|Dunleavy, Patrick]], "[https://blogs.lse.ac.uk/politicsandpolicy/duvergers-law-dead-parrot-dunleavy/ Duverger's Law is a dead parrot. Outside the USA, first-past-the-post voting has no tendency at all to produce two party politics]", June 18, 2012, British Politics and Policy at LSE

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[[Category:Types of democracy]]
[[Category:Elections]]
[[Category:Political party systems]]