RCV

Ranked-choice voting (RCV) is a voting system in which voters rank candidates in order of preference. In single-winner elections, RCV is commonly implemented as instant-runoff voting (IRV). In multi-winner elections, a related method is the single transferable vote (STV). RCV aims to ensure that elected candidates reflect broader support and to reduce spoiler effects and strategic voting associated with plurality voting.

In a typical IRV count, ballots are first tallied by each voter’s top choice. If a candidate exceeds a majority of active votes, that candidate wins. If no one has a majority, the candidate with the fewest first-choice votes is eliminated and those ballots are transferred to the next preferred candidate who remains in the race. The process repeats in rounds until a candidate achieves a majority. STV applies a quota for multiple seats and transfers surplus votes from elected candidates as well as votes from eliminated candidates, continuing until all seats are filled.

Advantages of RCV include producing winners with broad support, reducing spoiler effects, and allowing voters to express preferences without fear of wasting votes. Critics point to increased counting complexity, longer tabulation times, the possibility of ballot exhaustion if voters do not rank further candidates, higher administrative costs, and concerns about strategic ranking in some edge cases.

RCV has been adopted in various jurisdictions. Australia uses full preferential voting for federal elections. In the United States, several states and many cities use RCV for local or statewide races, including Maine and Alaska for certain elections, and cities such as San Francisco, Cambridge, and others for mayoral or council races.