An election worker goes over a ranked choice voting explanation card with a voter in New York, June 14.

An election worker goes over a ranked choice voting explanation card with a voter in New York, June 14.

Photo: Mary Altaffer/Associated Press

New York City voters went to the polls on June 22, but a week and a half later the winner of the Democratic mayoral primary remains unclear. That’s a big loss for the city’s new system of ranked-choice voting.

This was the first citywide election in New York to use ranked-choice voting, which passed by ballot measure in 2019. Proponents at Rank the Vote NYC promised the novel system would “foster more positive, issue-focused campaigns” and give voters “more choice.” Instead, New Yorkers endured a vicious campaign complete with questions about a leading candidate’s residency and allegations of fundraising and ethical violations.

Ranked-choice voting takes the simple concept of plurality voting—each voter selects his preferred candidate, the candidate with the most votes wins—and adds complexity that only a political theorist could love. Voters in New York City were offered the chance to rank as many as five candidates. No candidate received more than 50% of first-place votes, so the lowest-ranking candidates are being eliminated and their next-choice votes reallocated as if they were the first choice. The process continues until one candidate has a majority of remaining ballots.

On Wednesday the New York City Board of Elections announced unofficial totals showing that Brooklyn Borough President Eric Adams and former Sanitation Commissioner Kathryn Garcia were the last two candidates standing after nine elimination rounds. Mr. Adams has 51.1% of the remaining vote while Ms. Garcia has 48.9%. A mere 14,755 votes separate the two candidates, with 125,000 absentee ballots still to count. The Board of Elections was forced to revise an earlier tally after acknowledging that some 135,000 test ballots were wrongly included in the unofficial tally.

While Mr. Adams presently has the lead, and in the first round received more than 100,000 more votes than Ms. Garcia, the complexity of the system means he could still lose. This concern may have animated the comments of former Gov. David Paterson, who said: “I’m not ranking anybody, because I don’t like ranked choice voting. . . . As a matter of fact, if Eric Adams gets the most votes and somehow doesn’t turn out to be the mayor, I’m coming out of retirement.”

It sounds confusing because it is. Voters in other jurisdictions have often dealt with their confusion by staying home. Jason McDaniel, a political scientist at San Francisco State University, studied nearly two decades of election data in San Francisco, both before and after the city adopted a ranked-choice voting system similar to the one used in New York. His analysis found that “turnout declines among African-American and white voters” were “significantly correlated with adoption of RCV.” The system also “exacerbated disparities in voter turnout between those who are already likely to vote and those who are not, including younger voters and those with lower levels of education.”

Twitter users may find the idea intuitive. The general public does not.

Ranked-choice voting has also often failed to deliver on its signature promise of producing true “majority” candidates, as a consequence of a phenomenon called ballot exhaustion. Ballot exhaustion occurs when a voter ranks only candidates who are eliminated from consideration in a subsequent round of vote tabulation.

The ballot of a New York primary voter who chose progressive Scott Stringer and ranked no other candidate, for instance, would be “exhausted” once Mr. Stringer has been eliminated. That voter’s ballot wouldn’t be included in the final vote tally. This isn’t an isolated occurrence: As of the ninth round of tabulation in New York, unofficial totals show that more than 117,000 “exhausted” ballots have been discarded.

The Maine Policy Institute, a nonpartisan think tank, studied 96 different ranked-choice elections in which multiple rounds of tabulation were necessary to declare a winner. The study found the winning candidate “failed to receive a true majority 61 percent of the time.” In a 2010 municipal election in San Francisco, the winning candidate for the Board of Supervisors received less than 25% of the total votes cast; 60% of all ballots cast were discarded for the final tabulation.

Ranked-choice voting remains relatively rare in the U.S., existing in several municipalities as well as in Maine (via a 2016 ballot measure) and Alaska (via a 2020 ballot measure). Its recent spread hasn’t happened organically, but thanks to millions of dollars spent on ballot campaigns by a handful of donors, including Texas billionaires John and Laura Arnold. The campaign committee to pass ranked-choice voting in New York spent more than $2 million, drowning out objections from the City Council’s powerful Black, Latino and Asian Caucus.

Money can’t buy everything. Last fall, the Arnolds’ Action Now Initiative and several other donors spent more than $10 million promoting a ranked-choice voting ballot measure in Massachusetts. They lost by nearly 10 points.

New York’s rocky ranked-choice debut may deter others who are thinking about adopting the system. Expect repeal legislation in the City Council to gain momentum. The old saying still applies: If it ain’t broke, don’t fix it.

Mr. Saltsman is managing director and Ms. Paxton director of research and coalitions at the Employment Policies Institute.

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