Bullet voting
Encyclopedia
Bullet voting is a tactic in which the voter only selects one candidate, despite the option to indicate a preference for other candidates. They might do this either because it is easier than evaluating all the candidates, or (depending on the voting system
Voting system
A voting system or electoral system is a method by which voters make a choice between options, often in an election or on a policy referendum....

 in use) as a form of tactical voting
Tactical voting
In voting systems, tactical voting occurs, in elections with more than two viable candidates, when a voter supports a candidate other than his or her sincere preference in order to prevent an undesirable outcome.It has been shown by the Gibbard-Satterthwaite theorem that any voting method which is...

.

If enough voters bullet vote, almost any voting system
Voting system
A voting system or electoral system is a method by which voters make a choice between options, often in an election or on a policy referendum....

 functions like a plurality voting system
Plurality voting system
The plurality voting system is a single-winner voting system often used to elect executive officers or to elect members of a legislative assembly which is based on single-member constituencies...

. This is generally considered a poor result, as many voting systems are intended as reforms or improvements that avoid or minimize some alleged disadvantages of plurality (aka first past the post). However, if voters bullet vote as a conscious strategy to express their meta
Meta
Meta- , is a prefix used in English to indicate a concept which is an abstraction from another concept, used to complete or add to the latter....

-preference that candidates with strong support are preferable to "compromise" candidates with broad support, it may not be a problem.

This tactic is possible in any voting system that does not require ranking all candidates. In practice, this is the majority of voting systems as actually implemented (as opposed to in theory), since to reject ballots that do not rank all candidates risk an excessive number of spoiled ballots
Spoilt vote
'Bold text'In voting, a ballot is considered to be spoilt, spoiled, void, null, informal or stray if it is regarded by the election authorities to be invalid and thus not included in the tally during vote counting. This may be done accidentally or deliberately...

. However, it is mainly an issue in voting systems that reward this tactic—primarily approval voting
Approval voting
Approval voting is a single-winner voting system used for elections. Each voter may vote for as many of the candidates as the voter wishes. The winner is the candidate receiving the most votes. Each voter may vote for any combination of candidates and may give each candidate at most one vote.The...

, and to a lesser extent range voting
Range voting
Range voting is a voting system for one-seat elections under which voters score each candidate, the scores are added up, and the candidate with the highest score wins.A form of range voting was apparently used in...

—and in those that do not significantly penalize it—primarily instant-runoff voting
Instant-runoff voting
Instant-runoff voting , also known as preferential voting, the alternative vote and ranked choice voting, is a voting system used to elect one winner. Voters rank candidates in order of preference, and their ballots are counted as one vote for their first choice candidate. If a candidate secures a...

 and a non-standard form of Borda count
Borda count
The Borda count is a single-winner election method in which voters rank candidates in order of preference. The Borda count determines the winner of an election by giving each candidate a certain number of points corresponding to the position in which he or she is ranked by each voter. Once all...

.

Candidates may seek to encourage bullet voting in certain situations. One example is where there is a Bloc voting
Plurality-at-large voting
Plurality-at-large voting is a non-proportional voting system for electing several representatives from a single multimember electoral district using a series of check boxes and tallying votes similar to a plurality election...

election for two seats of the same office, and there are several candidates (say A, B, and C). Voters in such a situation typically have two votes. Candidate A encourages his voters to vote only for him and not use their second vote. If the second vote is cast for B or C, it helps A's opponents. The situation is most pronounced where A is of one party and B and C are of another party. If voters from B and C's party vote for them, while A's partisans cast one vote for A and split their second vote between B and C, A is significantly disadvantaged.
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