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[[File:2D election example with vote splitting and spoiler effect.png]]
 
This is an example simulation of an election on a 2-dimensional [[political spectrum]] (such as the [https://www.politicalcompass.org/ Political Compass], [https://www.nolanchart.com/survey-php Nolan chart], [[W:Pournelle chart|Pournelle chart]], etc.; it doesn't matter what the actual axes are.)
 
There are 3000 voters (blueblack dots), 3 candidates (redcolored dots), and voters vote honestly, supporting the candidates who are most similar to them ideologically (nearest distance).
*C (green) is a partisan candidate on the right
*A (blue) is another partisan candidate, this time on the left
** C wins under [[First Past the Post electoral system|first-past-the-post voting]], since A and B split the votes of the left wing of the electorate.
*AB (orange) is anothera partisanmoderate candidate, onand the leftbest representative of the average voter
 
** A wins under [[Instant-runoff voting|Instant-Runoff Voting]] ("Ranked-Choice Voting"), after B is eliminated for not having enough first-preference votes, leaving A and C (and A is slightly closer to the center, so more people in the center support A over C).
== FPTP ==
*B is a moderate candidate, and the best representative of the average voter
 
** B wins under [[Score Voting]] (with normalized ballots), as they are the highest-rated overall by the voters.
C wins under [[First Past the Post electoral system|first-past-the-post voting]], since A and B split the votes of the left wing of the electorate. (If A hadn't run, then B would have won. If B hadn't run, then A would have won. But since they both ran in the same election, C won instead.)
** B also wins under [[Condorcet method|Condorcet methods]], as B would beat both A and C in head-to-head elections.
[[File:2D election example A vs B vs C.png]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
|x=A, B, C
|y=1031, 861, 1108
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
 
== IRV ("RCV") / Exhaustive Ballot ==
 
A wins under [[Instant-runoff voting|Instant-Runoff Voting]] ("Ranked-Choice Voting"), after B is eliminated for not having enough first-preference votes, leaving A and C. (A is slightly closer to the center, so more people in the center support A over C.)
 
First round is the same as plurality:
 
[[File:2D election example A vs B vs C.png]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
|x=A, B, C
|y=1031, 861, 1108
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
 
 
 
Second round after B is eliminated:
 
[[File:2D election example A vs C.png]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
|x=A, B, C
|y=1619, 0, 1381
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
[[W:Exhaustive ballot|Exhaustive ballot]] behaves the same way, since it uses the same elimination rule as IRV, only held using multiple single-mark ballot runoffs instead of using a ranked ballot.
 
== Top-two runoff / Open primary / Contingent Vote ==
 
A wins under [[Runoff voting|top-two runoff]] or an [[W:Nonpartisan blanket primary|open primary]]. A and C have the most votes and proceed to the runoff. (None of the candidates gets over 50% in the first round.) A is slightly closer to the center, so more people in the center support A over C in the runoff.
 
First round is the same as plurality:
 
[[File:2D election example A vs B vs C.png]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes [%]|type=rect
|x=A, B, C
|y=34.37, 28.70, 36.93
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
 
 
 
Second round after B is eliminated:
 
[[File:2D election example A vs C.png]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes [%]|type=rect
|x=A, B, C
|y=53.97, 0.00, 46.03
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
[[W:Contingent vote|Contingent vote]] behaves the same way, except the runoff election is held automatically based on ranked ballots.
 
== Score ==
 
[[File:2D election example Scores for A, B, C.png|800x800px]]
 
B wins under [[Score Voting]] (with normalized ballots), as they are the highest-rated overall by the voters. (Dark-colored voters gave that candidate a maximum score, white-colored voters gave them a minimum score.)
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Total score|type=rect
|x=A, B, C
|y=1391.735, 2206.151, 1251.829
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
 
== Condorcet ==
 
B also wins under [[Condorcet method|Condorcet methods]], as B would beat both A and C in head-to-head elections.
 
A vs B:
 
[[File:2D election example A vs B.png]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
|x= A, B, C
|y= 1031, 1969, 0
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
 
 
 
B vs C:
 
[[File:2D election example B vs C.png]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
|x= A, B, C
|y= 0, 1892, 1108
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
 
== STAR ==
 
B also wins under [[STAR voting|STAR Voting]]. The first round is the same as Score, so the top-two winners are A and B (since A is slightly closer to the center than C):
 
[[File:2D election example Scores for A, B, C.png|800x800px]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Total score|type=rect
|x=A, B, C
|y=1391.735, 2206.151, 1251.829
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
 
B is then preferred over A by a 66% majority.
 
[[File:2D election example A vs B.png]]
 
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
|x= A, B, C
|y= 1031, 1969, 0
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
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