Instant-runoff voting (IRV), also known as the alternative vote (AV), transferable vote, (single-seat) ranked-choice voting (RCV), or preferential voting, is a voting system used in single-seat elections when there are more than two candidates. Instead of voting only for a single candidate, in IRV voters can rank the candidates in order of preference. Ballots are initially counted for each elector's top choice. If a candidate secures more than half of these votes, that candidate wins. Otherwise, the candidate in last place is eliminated and removed from consideration. The top remaining choices on all the ballots are then counted again. This process repeats until one candidate is the top remaining choice of a majority of the voters. When the field is reduced to two, it has become an "instant runoff" that allows a comparison of the top two candidates head-to-head.
