First-past-the-post voting

First-past-the-post (FPTP) — also called choose-one, first-preference plurality (FPP), or simply plurality — is a single-winner voting rule. Each voter marks one candidate as their favorite, or first-preference, and the candidate with more first-preference votes than any other candidate (a plurality) is elected, even if they do not have more than half of votes (a majority). FPP has been used to elect part of the British House of Commons since the Middle Ages before spreading throughout the British Empire, usually in conjunction with plurality block voting. Throughout the 20th century, the former British colonies of Australia and New Zealand and many other countries that were using FPP abandoned it in favor of other electoral systems. FPP is still used in the majority of US states for most elections. However, the combination of partisan primaries and a two-party system in these jurisdictions means that most American elections behave effectively like two-round systems, in which the first round chooses two main contenders (of which one of them goes on to usually receive a majority of votes).