Relative majority

A plurality vote (in North America) or relative majority (in the United Kingdom) describes the circumstance when a candidate or proposition polls more votes than any other, but does not receive a majority. For example, if 100 votes were cast, including 45 for Candidate A, 30 for Candidate B and 25 for Candidate C, then Candidate A received a plurality of votes but not a majority. In some votes, the winning candidate or proposition may have only a plurality, depending on the rules of the organization holding the vote.

In international institutional law, a "simple majority" (also a "majority") vote is more than half of the votes cast (disregarding abstentions) among alternatives; a "qualified majority" (also a "supermajority") is a number of votes above a specified percentage (e.g. two-thirds); a "relative majority" (also a "plurality") is the number of votes obtained that is greater than any other option; and an "absolute majority" is a number of votes "greater than the number of votes that possibly can be obtained at the same time for any other solution", when voting for multiple alternatives at a time.

Henry Watson Fowler suggests that the American terms "plurality" and "majority" offer single-word alternatives for the corresponding two-word terms in British English, "relative majority" and "absolute majority", and that in British English "majority" is sometimes understood to mean "receiving the most votes" and can therefore be confused with "plurality".William Poundstone observes that systems which allow choosing by a plurality of votes are more vulnerable to the spoiler effect—where two or more similar choices each draw fewer votes than an dissimilar choice that would have lost to any individual similar choice on its own—than systems which require a majority.

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