Ranked-choice voting (RCV), also called instant-runoff voting in single-winner contests, lets voters express preferences beyond a single candidate. Maine uses it for federal elections; Alaska uses it for state and federal races; New York City and dozens of other cities use it for municipal elections.
Proponents argue RCV reduces "spoiler" effects, encourages broader-appeal campaigning, and yields majority winners without the cost of a second-round runoff. Critics argue it is harder for voters to understand, can produce non-monotonic outcomes in unusual edge cases, and that ballot exhaustion (voters who don't rank enough candidates) can yield winners with less than a true majority of original ballots cast.
The practical question for any jurisdiction is whether the trade-offs — added ballot complexity for richer expression of preference — produce better representation of the median voter than the existing plurality system.