Editing Plurality voting (section)

== Plurality voting procedures ==

=== Single-winner and single-member systems ===
{{Further|First-past-the-post voting}}
In single-winner plurality voting ([[First-past-the-post voting|first-past-the-post]]), each voter is allowed to vote for only one candidate, and the winner of the election is the candidate who represents a plurality of voters or, in other words, received more votes than any other candidate. In an election for a single seat, such as for [[President (government title)|president]] in a [[presidential system]], voters may vote for one candidate from a list of the candidates who are competing, and the winner is whichever candidate receives the highest number of votes. Compare first-past-the-post to a ''majority'' system, the [[two-round system]], where usually the top two candidates in the first ballot progress to the second round, also called the runoff. A runoff is by default not held, if a candidate already received an absolute majority in the first ballot (more than half of votes), and in the second ballot, where there are only two candidates, one of the candidates will (except for a tie) receive a majority. Under plurality rules, the candidates are not at any point in the election required to have majority support.

In an election for a legislative body with single-member seats, each voter in a geographically defined [[constituency|electoral district]] may vote for one candidate from a list of the candidates who are competing to represent that district. Under the plurality system, the winner of the election then becomes the representative of the whole electoral district and serves with representatives of other electoral districts. That makes plurality voting among the simplest of all electoral systems for voters and vote counting officials;<ref name=":7" /> however, the drawing of district boundary lines can be [[Gerrymandering|contentious]] in the plurality system (see [[gerrymandering]]). The system is also independent of parties; the party with the most votes overall may not win the most seats overall ([[electoral inversion]]). Note that issues arising from single-member districts are still in place with majority voting systems, like the two-round system and [[instant-runoff voting]] too.

The same principle used in single-winner plurality voting (electing the candidate with the most votes) is also used in [[approval voting]], however with very different effects, as voters can choose to support as many or few candidates as they choose, not just one. For this reason, approval voting is usually distinguished from plurality voting, while technically being a sub-type of it.

=== Multi-winner systems ===
Multi-member plurality elections are only slightly more complicated. Where ''n'' is the number of seats in the district, the ''n'' candidates who get more votes than the others are elected;<ref>{{Cite journal |last1=Dulay |first1=Dean |last2=Go |first2=Laurence |date=2021-08-01 |title=First among equals: The first place effect and political promotion in multi-member plurality elections |journal=Journal of Public Economics |language=en |volume=200 |pages=104455 |doi=10.1016/j.jpubeco.2021.104455 |issn=0047-2727 |s2cid=236254332 |doi-access=free}}</ref> the winners are the ''n'' candidates with the largest number of votes. The rules may allow the voter to vote for one candidate, for a number of candidates more than one but less than ''n'', for as many as ''n'' candidates, or some other number.

When voters may vote for only one candidate, it is called the [[single non-transferable vote]]. While seemingly most similar to [[First-past-the-post voting|first-past-the-post]], in effect it is a semi-proportional system allowing for mixed representation in one district, and representation of both majority parties and electoral minorities within a district.

When voters can vote for one or more candidates, but in total less than the number of winners, it is called [[limited voting]].

The multi-winner version considered to be the extension of first-past-the-post to multi-winner cases is [[plurality block voting]]. Here voters may vote for as many candidates as there are seats to fill, which means usually candidates from the largest party will fill all the seats in the district.

The party-list version of plurality voting in multi-member districts is called [[general ticket|party block voting]]. Here the party receiving a plurality of votes wins all of the seats available.

=== Ballot types ===
[[File:Plurality ballot.svg|thumb|right|An example of a plurality ballot]]
Generally, plurality ballots can be categorized into two forms. The simplest form is a blank ballot in which the name of a candidate(s) is written in by hand. A more structured ballot will list all the candidates and allow a mark to be made next to the name of a single candidate (or more than one, in some cases); however, a structured ballot can also include space for a [[write-in candidate]].

=== Examples ===

==== Single-winner ====
This is a general example for single-winner plurality voting ("first-past-the-post"), using population percentages taken from one [[U.S. state|state]] for illustrative purposes.
{{Tenn voting example}}

If each voter in each city naively selects one city on the ballot (Memphis voters select Memphis, Nashville voters select Nashville, and so on), Memphis will be selected, as it has the most votes 42%. The system does not require that the winner have a [[majority]], only a plurality. Memphis wins because it has the most votes even though 58% of the voters in the example preferred Memphis least. The opposite result would occur in [[Instant-runoff voting|instant-runoff]], where Knoxville (the city furthest to the east, and the "second-worst" choice) would accumulate a majority from vote transfers from voter who initially voted for Chattanooga and Nashville. Nashville is the [[majority-preferred winner]], and as a result would be elected by any [[Condorcet method]].

==== Multi-winner ====
Candidates are running in a 3-member district of 10 000 voters.

Under non-transferable (and non-cumulative) plurality voting, each voter may cast no more than one vote for a single candidate, even if they have multiple votes to cast.

* Under [[Plurality block voting|block voting]], the standard multiple-winner non-transferable vote election method, voters may cast 3 votes (but do not have to)
* Under [[limited voting]], voters may cast 2 votes maximum
* Under the single non-transferable vote, voters may cast 1 vote

Party A has about 35% support among the electorate (with one particularly well-liked candidate), Party B around 25% (with two well-liked candidates) and the remaining voters primarily support independent candidates, but mostly lean towards party B if they have to choose between the two parties. All voters [[Sincere voting|vote sincerely]]; there is no tactical voting. (Percentage of votes under MNTV and Limited Voting is the percentage of voters who voted for the candidate, not the percentage of votes cast.)
{| class="wikitable"
! rowspan="3" |Candidate
! colspan="2" rowspan="3" |Party
! colspan="8" |Multiple non-transferable vote
! colspan="4" rowspan="2" |Single non-transferable vote
|-
! colspan="4" |Plurality block voting
! colspan="4" |Limited voting
|-
!Votes
!%
! colspan="2" |Elected?
!Votes
!%
! colspan="2" |Elected?
!Votes
!%
! colspan="2" |Elected?
|-
|Candidate A1
| style="background:#D10000" |
|Party A
|'''3700'''
|'''37%'''
|'''1.'''
|'''Yes'''
|'''3500'''
|'''35%'''
|'''1.'''
|'''Yes'''
|'''2000'''
|'''20%'''
|'''1.'''
|'''Yes'''
|-
|Candidate A2
| style="background:#D10000" |
|Party A
|'''3600'''
|'''36%'''
|'''2.'''
|'''Yes'''
|'''1900'''
|'''19%'''
|'''2.'''
|'''Yes'''
|800
|8%
|4.
|
|-
|Candidate A3
| style="background:#D10000" |
|Party A
|'''3555'''
|'''36%'''
|'''3.'''
|'''Yes'''
|1800
|18%
|4.
|
|700
|7%
|7.
|
|-
|Candidate B1
| style="background:#0008A5" |
|Party B
|2600
|26%
|4.
|
|'''1950'''
|'''20%'''
|'''3.'''
|'''Yes'''
|'''1100'''
|'''11%'''
|'''2.'''
|'''Yes'''
|-
|Candidate B2
| style="background:#0008A5" |
|Party B
|2500
|25%
|5.
|
|1750
|18%
|4.
|
|'''900'''
|'''9%'''
|'''3.'''
|'''Yes'''
|-
|Candidate B3
| style="background:#0008A5" |
|Party B
|2400
|24%
|6.
|
|1425
|14%
|7.
|
|400
|4%
|12.
|
|-
|Candidate I1
|
|Independent
|2300
|23%
|8.
|
|1400
|14%
|8.
|
|800
|8%
|4.
|
|-
|Candidate I2
|
|Independent
|2395
|24%
|7.
|
|1500
|15%
|6.
|
|800
|8%
|4.
|
|-
|Candidate I3
|
|Independent
|1900
|19%
|9.
|
|1300
|13%
|9.
|
|700
|7%
|7.
|
|-
|Candidate I4
|
|Independent
|1800
|15%
|10
|
|1200
|12%
|10.
|
|700
|7%
|7.
|
|-
|Candidate I5
|
|Independent
|650
|7%
|11.
|
|625
|6%
|11.
|
|600
|6%
|10.
|
|-
|Candidate I6
|
|Independent
|600
|6%
|12.
|
|550
|6%
|12.
|
|500
|5%
|11.
|
|-
| colspan="3" |''TOTAL votes cast''
|28000
|
|
|
|19000
|
|
|
|10000
|
|
|
|-
| colspan="3" |TOTAL possible votes
|30000
|
|
|
|20000
|
|
|
|10000
|
|
|
|-
| colspan="3" |Voters
|10000
|100%
|
|
|10000
|100%
|
|
|10000
|100%
|
|
|}
Under all three versions of multi-winner plurality voting, the three most popular candidates according to voters' first preferences are elected, regardless of party affiliation, but with three different results.

* Under block voting ([[Plurality block voting]]), the three candidates of the most popular party are elected if its supporters vote along party lines. In this case a party with only 35 percent support took all the seats.
* Under limited voting, it is most likely that the party with a plurality takes two seats (or the same number of seats as the number of votes each voter has), and another less-popular party receives the remaining seat(s).
* Under the single non-transferable vote (like in the other two methods) the number of seats are sometimes not proportionately allocated. Over-optimism (running too many candidates) and vote splitting is harshly punished. But each popular party that runs one candidate is assured of success to that degree anyway. In this case, even though the most-popular party ran three and risked vote splitting, it did elect one member.
* In a situation where three are to be elected and [[Single transferable vote|single transferable voting]] is used, ranked votes are used and each voter has just one vote, any candidate that accumulates about 25 percent of the vote will be elected and supporters of one party even if initially spread over two or three candidates can concentrate behind only one or two, just the candidates of the party that are electable. The plurality rule applies in that the most-popular candidates of the party are the ones that are elected.