How does ranked-choice voting work?

In ranked-choice voting, voters rank candidates as first, second, third and so on, instead of choosing only one. If a candidate gets more than 50 percent of first choices, that candidate wins, as in any other election. If nobody does, a series of instant runoff rounds begins: the candidate with the fewest votes is eliminated, and ballots that ranked that candidate first count for their next choice. This repeats until one candidate holds a majority. The version described here, for a single winner, is also called instant-runoff voting. [1] [2] [3]

The Alaska Division of Elections describes the count in rounds. In round one, all first choices are counted. If a candidate has 50 percent plus one vote, that candidate wins and counting stops. If not, the candidate with the fewest votes is eliminated. Voters who picked that candidate have their ballots moved to their next choice, while voters whose first choice remains in the race keep their vote with that candidate. Votes are counted again, and the process continues until two candidates are left, and the one with the most votes wins. [4]

Ballotpedia notes that details, such as how many candidates are eliminated in each round, can vary by jurisdiction. Its example uses six hypothetical mayoral candidates, where the one with the fewest first-preference votes is dropped first and the second preferences on those ballots are added to the remaining totals. [2]

Supporters such as Cal RCV point out that this happens automatically on election night, so voters do not have to return for a separate runoff election. They also contrast it with single-choice voting, in which a candidate can win with 20 or 30 percent of the vote if no one else gets more. [5]

Voters do not have to rank every candidate. Alaska's instructions say to rank as many or as few as you like and to fill in no more than one oval per candidate and per column. If you vote for only one candidate, your vote stays with that candidate throughout the count. [4] [1]

FairVote says that ranking a second choice does not hurt your first choice. A lower choice is only used if your higher choice has been eliminated. [1]

Ranked ballots can also fill several seats at once, which is called proportional or multi-winner ranked-choice voting. Voters rank candidates in the same way, but a winning candidate must reach a threshold based on the number of seats rather than a majority. Cal RCV gives the threshold as one divided by the number of seats plus one, so three seats require just over 25 percent and four seats just over 20 percent. [5] [1]

When a candidate gets more votes than needed, a proportional share of those voters' next choices is counted toward other winners instead of being discarded. If no further candidate reaches the threshold, the lowest candidate is eliminated and those votes transfer to next choices. [5]