Editing Spoiler effect (section)

=== Notable unintentional spoilers ===
An unintentional spoiler is one that has a realistic chance of winning but falls short and affects the outcome of the election. Some third-party candidates express ambivalence about which major party they prefer and their possible role as spoiler<ref name=":133">{{Cite news |last=Selk |first=Avi |date=2021-11-25 |title=Analysis {{!}} Green Party candidate says he might be part alien, doesn't care if he's a spoiler in Ohio election |url=https://www.washingtonpost.com/news/the-fix/wp/2018/08/09/green-party-candidate-says-he-might-be-part-alien-doesnt-care-if-he-spoils-ohio-election/ |access-date=2023-07-21 |newspaper=[[The Washington Post]] |language=en-US |issn=0190-8286}}</ref><ref name=":032">{{Cite web |last1=Merica |first1=Dan |last2=Slodysko |first2=Brian |date=2024-08-19 |title=Republicans scrambled to get Cornel West on the Arizona ballot. The left-wing academic is OK with it |url=https://apnews.com/article/republican-lawyers-cornel-west-arizona-88cd1b4f698715a3071a93b5e1526074 |access-date=2024-08-27 |website=AP News |language=en}}</ref> or deny the possibility.<ref name="means2">{{cite web |author=Means |first=Marianne |date=February 4, 2001 |title=Opinion: Goodbye, Ralph |url=http://seattlepi.nwsource.com/opinion/means4.shtml |url-status=dead |archive-url=https://web.archive.org/web/20020526010840/http://seattlepi.nwsource.com/opinion/means4.shtml |archive-date=May 26, 2002 |website=[[Seattle Post-Intelligencer]] |df=mdy}}</ref>

==== 2009 Burlington mayoral election ====
In [[2009 Burlington mayoral election|Burlington, Vermont's second IRV election]], spoiler [[Kurt Wright]] knocked out Democrat [[Andy Montroll]] in the second round, leading to the election of [[Bob Kiss]], despite the election results showing most voters preferred Montroll to Kiss.<ref name="Stensholt">{{Cite journal |last=Stensholt |first=Eivind |date=2015-10-07 |title=What Happened in Burlington? |url=https://ideas.repec.org//p/hhs/nhhfms/2015_026.html |journal=Discussion Papers |language=en |pages=13 |quote=There is a Condorcet ranking according to distance from the center, but Condorcet winner M, the most central candidate, was squeezed between the two others, got the smallest primary support, and was eliminated.}}</ref> The results of every possible one-on-one election can be completed as follows:
{| class="wikitable"
![[File:Democratic_Disc.svg|60x60px]]
!Andy Montroll ([[Democratic Party (United States)|D]])
|'''6262 (Montroll) –'''
591 (Simpson)
|'''4570 (Montroll) –'''
2997 (Smith)
|'''4597 (Montroll) –'''
3664 (Wright)
|'''4064 (Montroll) –'''
3476 (Kiss)
|[[Copeland score|'''4/4 Wins''']]
|-
! [[File:Progressive Disk.png|60x60px]]
!Bob Kiss ([[Vermont Progressive Party|P]])
|'''5514 (Kiss) –'''
844 (Simpson)
|'''3944 (Kiss) –'''
3576 (Smith)
|'''4313 (Kiss) –'''
4061 (Wright)
|[[Copeland score|'''3/4 Wins''']]
|'''''IRV winner'''''
|-
![[File:Republican_Disc.svg|60x60px]]
!Kurt Wright ([[Republican Party (United States)|R]])
|'''5270 (Wright) –'''
1310 (Simpson)
|'''3971 (Wright) –'''
3793 (Smith)
|[[Copeland score|'''2/4 Wins''']]
| colspan="2" |'''''Spoiler for Montroll'''''
|-
![[File:Independent Candidate Disc.svg|60x60px]]
!Dan Smith ([[Independent politician|I]])
|'''5570 (Smith) –'''
721 (Simpson)
|[[Copeland score|'''1/4 Wins''']]
| colspan="3" |
|-
![[File:Green_Disc.svg|60x60px]]
!James Simpson ([[Green Party of the United States|G]])
|[[Copeland score|'''0/4 Wins''']]
| colspan="4" |
|}
This leads to an overall preference ranking of:

# Montroll – defeats all candidates below, including Kiss (4,064 to 3,476)
# Kiss – defeats all candidates below, including Wright (4,313 to 4,061)
# Wright – defeats all candidates below, including Smith (3,971 to 3,793)
# Smith – defeats Simpson (5,570 to 721) and the write-in candidates

Montroll was therefore preferred over Kiss by 54% of voters, over Wright by 56%, and over Smith by 60%. Had Wright not run, Montroll would have won instead of Kiss.<ref name="Stensholt" /><ref>{{Cite web|url=https://www.electionscience.org/library/irv-and-core-support/|title=IRV and Core Support|website=The Center for Election Science|language=en-US|access-date=December 4, 2019}}</ref>

Because all ballots were fully released, it is possible to reconstruct the winners under other voting methods. While Wright would have won under [[Plurality voting|plurality]], Kiss won under [[Instant-runoff voting|IRV]], and would have won under a [[two-round system|two-round vote]] or a traditional [[nonpartisan blanket primary]]. Montroll, being the [[Condorcet winner criterion|majority-preferred candidate]], would have won if the ballots were counted using [[ranked pairs]] (or any other [[Condorcet method]]).<ref name=":gsmc">{{Cite journal |last1=Graham-Squire |first1=Adam T. |last2=McCune |first2=David |date=2023-06-12 |title=An Examination of Ranked-Choice Voting in the United States, 2004–2022 |journal=Representation |volume=61 |language=en |pages=1–19 |doi=10.1080/00344893.2023.2221689|arxiv=2301.12075 }}</ref>

==== 2022 Alaska's at-large congressional district special election ====
In [[2022 Alaska's at-large congressional district special election|Alaska's first-ever IRV election]], [[Nick Begich III|Nick Begich]] was eliminated in the first round to advance [[Mary Peltola]] and [[Sarah Palin]]. However, the pairwise comparison shows that Begich was the [[Condorcet winner criterion|Condorcet winner]] while Palin was both the [[Condorcet loser criterion|Condorcet loser]] and a spoiler:<ref name="Analysis Alaska2" />
<!--- Tables inside a table in order to get both to sit next to each other --->
{| 
|+
|-
|
{| class="wikitable" 
|+Pairwise comparison matrix by vote totals<ref name="Clelland">{{Cite arXiv |last=Clelland |first=Jeanne N. |date=2023-02-28 |title=Ranked Choice Voting And the Center Squeeze in the Alaska 2022 Special Election: How Might Other Voting Methods Compare? |page=6 |class=cs.CY |eprint=2303.00108v1 |language=en}}</ref><ref name="Analysis Alaska2">{{Cite arXiv |last1=Graham-Squire |first1=Adam |last2=McCune |first2=David |date=2022-09-11 |title=A Mathematical Analysis of the 2022 Alaska Special Election for US House |page=2 |class=econ.GN |eprint=2209.04764v3 |language=en |quote=Since Begich wins both … he is the Condorcet winner of the election … AK election also contains a Condorcet loser: Sarah Palin. … she is also a spoiler candidate}}</ref>
!
!Begich
!Peltola
!Palin
|-
!Begich
| -
|'''88,126'''
|'''101,438'''
|-
!Peltola
|79,486
| -
|'''91,375'''
|-
!Palin
|63,666
|86,197
| -
|}

|
{| class="wikitable" style="float:right; margin-left:1em;
|+ Pairwise as a percentage
!Winner
!
!Loser
!Winner
!Loser
|-
|'''Begich'''
|vs.
|'''Peltola'''
|52.6%
|vs. 47.4%
|-
|'''Begich'''
|vs.
|'''Palin'''
|61.4%
|vs. 38.6%
|-
|'''Peltola'''
|vs.
|'''Palin'''
|51.5%
|vs. 48.5%
|}
|}

In the wake of the election, a poll found 54% of Alaskans, including a third of Peltola voters, supported a repeal of RCV.<ref name=":2">{{cite web |last=Baruth |first=Philip |date=March 12, 2009 |title=Voting Paradoxes and Perverse Outcomes: Political Scientist Tony Gierzynski Lays Out A Case Against Instant Runoff Voting |url=http://vermontdailybriefing.com/?p=1213 |url-status=dead |archive-url=https://web.archive.org/web/20110726125814/http://vermontdailybriefing.com/?p=1213 |archive-date=July 26, 2011 |publisher=Vermont Daily Briefing}}</ref><ref name="repeal2">{{cite web |last=Slota |first=Bianca |date=March 2, 2010 |title=Burlington voters repeal IRV |url=http://www.wcax.com/story/12074080/burlington-voters-repeal-irv |archive-url=https://web.archive.org/web/20160409132306/http://www.wcax.com/story/12074080/burlington-voters-repeal-irv |archive-date=April 9, 2016 |access-date=March 28, 2016 |publisher=[[WCAX-TV|Wcax.com]]}}</ref><ref name="rutland_herald">{{cite web |last=Barlow |first=Daniel |date=April 27, 2010 |title=Instant run-off voting experiment ends in Burlington : Rutland Herald Online |url=http://www.rutlandherald.com/article/20100427/NEWS03/4270339/1004/NEWS03 |url-status=dead |archive-url=https://web.archive.org/web/20160304055602/http://www.rutlandherald.com/article/20100427/NEWS03/4270339/1004/NEWS03 |archive-date=March 4, 2016 |access-date=April 1, 2016 |website=Rutlandherald.com}}</ref> Observers noted such pathologies would have occurred under Alaska's previous primary system as well, leading several to suggest Alaska adopt any one of [[Comparison of electoral systems|several alternatives]] without this behavior.<ref>{{Cite journal |last1=Felsenthal |first1=Dan S. |last2=Tideman |first2=Nicolaus |date=2014-01-01 |title=Interacting double monotonicity failure with direction of impact under five voting methods |url=https://www.sciencedirect.com/science/article/pii/S0165489613000723 |journal=Mathematical Social Sciences |volume=67 |pages=57–66 |doi=10.1016/j.mathsocsci.2013.08.001 |issn=0165-4896|url-access=subscription }}</ref>