On Tuesday, New York City residents cast their ballots for their favorite candidate in mayoral primary. They also chose their second, third, fourth and fifth favorites.
That's because the country’s most populous city has changed the way voters cast their ballots in local elections, now using a system called ranked-choice voting.
While the method has been used in state elections in Maine and several cities across the country — including San Francisco and Minneapolis — Tuesday’s primary election is the largest-scale test for the system in the United States.
As the new election method gains momentum, here are the basics of ranked-choice voting:
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What is ranked-choice voting?
The method gives voters the option of ranking candidates on the ballot in order of their preference — one for their top choice, two for their second choice, and so on — rather than cast a single vote for one person.
How does ranked-choice voting work?
If a candidate draws more than 50% of first-choice votes, they are declared the winner. If no candidate received a majority of the first-preference votes, the candidate with the fewest first-preference votes is eliminated. Ballots listing the eliminated candidate as the first-choice are then reallocated to whichever candidate was listed as the voters' second preference. This process continues until one candidate draws over 50% of the adjusted top votes.
The voting process is especially useful for avoiding costly runoff elections in crowded races where the winning candidate often fails to get more than 50% of the vote.
NBC National Political Correspondent Steve Kornacki recently explained New York City’s new system on Andrea Mitchell Reports: “It’s an extremely complicated process, but the idea is the voters only have to go to the polls once. You mark off your top five choices, they work through them in rounds and eventually they will produce the winner of the democratic primary.”
The types of races and number of candidates eligible for ranking vary by jurisdiction. In New York City, voters can rank up to five candidates, while in San Francisco, voters can rank as many as 10 candidates.
Maine uses ranked-choice voting for all state-level primary elections and for presidential and U.S. Senate races. It doesn't use the method for state races, like legislative and gubernatorial elections, because the state supreme court ruled in 2017 that it runs afoul to the Maine Constitution.
How Ranked Choice Voting Works
The 2021 New York City Mayoral Election is the first citywide race to use the new voting system
Source: NYC Board of Elections • Andrew Williams / NBC
Where has it been used?
Ranked voting has gained some momentum since San Francisco first used the election system in 2004. In Nov. 2020, Alaska joined Maine as the only states to adopt ranked choice voting in federal elections. Major cities like Minneapolis, St. Paul and New York City have also signed on. Nevada, Hawaii, Kansas and Wyoming also used the method for voting in the 2020 Democratic presidential primaries.
As of May 2021, 21 counties and towns used ranked-choice voting in the most recent elections, with 52 more projected to use it in upcoming elections, according to FairVote, a nonpartisan organization advocating electoral reform. In Utah, 26 cities have opted-in to use ranked-choice voting in the next municipal election as part of a state-wide pilot program testing the system.
Internationally, it is used by voters in Australia, Ireland, New Zealand, Malta, Northern Ireland and Scotland.
What are the drawbacks and benefits?
Opponents of ranked choice voting claim the process is more confusing than plurality voting and delays results. The system requires voters to do a lot more research and makes races less predictable.
Transparency and trust are also potential problems. Ordinarily, candidates, the public and news organizations can see votes coming in, precinct by precinct, and know exactly who is leading and where their support is coming from.
Under the modern ranked choice system, the process of redistributing votes is done by computer. Outside groups will have a harder time evaluating whether the software sorted the ranked votes accurately.
And there may be instances where candidates who seem to have a comfortable lead in first-place votes on election night lose because relatively few voters rank them as their second or third choice. That could lead to people questioning the results at time when trust in the U.S. election process is already frail.
Proponents say the complications are worth the boon to democracy provided by the process. Because voters’ second, third or even fourth and fifth options are taken into account, voters have more flexibility to follow their heart, rather than vote strategically for a less-desirable but more viable candidate. It could also boost the chances of independent and third-party candidates.
The system also means the winning candidate has to draw broad support, which proponents say could decrease the level of vitriol in campaigning. As the Committee for Ranked Choice Voting put it: “you are less likely to rank as your second choice a candidate who has issued personal attacks against your favorite candidate.”
The Associated Press contributed to this report.