And a fundamentally new approach to how those voters choose a nominee — by ranking their top picks — is forcing the candidates to chart an unknown course in campaigning, making history only a limited barometer for how the coming months will unfold.

Andrew Yang, the former presidential hopeful, became the latest big name to throw his hat in the ring this month. He joined a field that already includes long-established elected officials such as City Comptroller Scott Stringer and Brooklyn Borough President Eric Adams. Wall Street executive Ray McGuire, attorney and MSNBC commentator Maya Wiley, former HUD Secretary Shaun Donovan, former nonprofit executive Dianne Morales and former sanitation commissioner Kathryn Garcia are among the two dozen or so candidates who have jumped into the ring.

Unlike in primaries past, the candidates may not be tumbling over each other to reach the top spot. Under the city's new ranked-choice voting system, contenders could begin forming coalitions around the issues central to their campaigns — and asking voters to consider supporting some of their competitors.

The new voting system, adopted through a ballot referendum in 2019, lets voters rank up to five candidates in order of preference instead of voting for just one. If no candidate gets more than 50 percent of the vote, a computerized system will eliminate the last place candidate and redistribute their votes to the voter’s second choice — a process that continues until someone tops 50 percent and takes the win.

A state senator from the Bronx, Gustavo Rivera, this week made the first ranked choice endorsement, naming Stringer as his first choice, and Morales, a progressive Afro-Latina, as his second. That’s likely to become a trend as it gives endorsers some political cover.

Morales said the new system is opening doors for campaigns like hers.“Candidates like me — political outsiders, first-timers, women of color — are often overlooked during our races,” she said.

Ranked-choice voting, its supporters say, decreases negative campaigning because candidates angling for second choice votes don’t want to alienate a rival’s supporters — and so far the race has been devoid of harsh attacks.

“It’s affecting how people are campaigning, and thus far we really haven’t seen people attack one another,” said Christina Greer, a political science professor at Fordham University. “I think it ultimately will devolve as people get desperate.”

The comity brought on by the voting overhaul is already showing its limits. Several candidates took shots at Yang when he entered the race — questioning his commitment to New York after POLITICO revealed he left the city at the height of the pandemic. On Monday, Stringer sent out a fundraising appeal going after McGuire, saying he needed donations to “compete with our opponent's millions in Wall Street contributions.”

There’s no consensus on which candidate will benefit most from the new system, but Adams has been the most vocal in pushing to delay it — arguing it will “disenfranchise” Black and Latino voters by adding an extra level of complexity to the process. A group of City Council members have sued to stop the voting overhaul.

In other cities that have tried ranked-choice voting, such as San Francisco, unusual alliances have developed between candidates. Political observers there, where the system has been in place since the early 2000s, say the approach is meant to encourage candidates to put their egos to the side — no small task for politicians — and focus more on building coalitions around issues.

Ranked-choice voting “was originally sold to San Franciscans as a way to promote finding common cause on issues in campaigns — making things more about issues than candidates,” said Alex Clemens, a veteran Bay Area political strategist and lobbyist with Lighthouse Public Affairs. “The real question is, has that worked?”

San Francisco is a tough political town, and elbow throwing is still a popular pastime among candidates vying for office. The classic qualities of a successful politician — good at retail, good at raising money and good at public speaking — are still likely to carry the day.

"The most compelling candidates, the best-funded candidates still tend to be the words that describe the winner,” Clemens said. “But coalitions have proven to be helpful in improving the chances of nonfrontrunners in the race."

The biggest adjustment for New York pols will likely be pointing to some of their competitors and admitting they’d do a good job as mayor.

"It takes a hell of an ego to say, 'I’m the only person who can or will do this good thing,'” Clemens said, advising candidates to identify others in the race that they feel would do well on a given issue. "That benefits political discourse. That takes it away from egos and refocuses campaigns on promoting issues that people talk about around their kitchen tables."

Greer said she’s “interested to see if people sort of link up, Survivor-style.”

Meanwhile, candidates have been building their campaign war chests, and three — Stringer, Adams and, most recently, Wiley — have met the threshold to get a big infusion of taxpayer matching funds.

With Republicans struggling to attract candidates — even billionaire John Catsimatidis, viewed as the party’s best hope, says he may switch parties and run as a Democrat instead — business leaders and real estate types have honed in on the Democratic race, hoping to sway it to a more moderate candidate.

Some have gotten behind McGuire, who brought in over $5 million with contributors including Wall Street and real estate executives and some prominent Republican donors. He is not participating in the public matching funds system, which imposes stricter donation limits. There’s even an organized push to get Republicans and unaffiliated voters to register as Democrats to swing the primary in a more moderate direction.

New York mayoral elections have never followed a predictable script. Incumbent Mayor Bill de Blasio, who is leaving office due to term limits, won the Democratic primary in 2013 after a late surge turned him from underdog to front runner, driven in part by the collapse of Anthony Weiner’s campaign in a sexting scandal. His predecessor, Mike Bloomberg, was elected as a Republican in 2001 in a race upended by the Sept. 11 attacks, which happened on what would have been primary day.

This year, there has been little public polling so far. Internal polls and a poll commissioned by an advocacy group have shown Yang with an early lead, in part a function of his name recognition. But between the pandemic, the drama surrounding the presidential election and the earlier campaign schedule, even likely voters have yet to fully tune in.

“People are just fatigued by electoral politics right now, I don’t think people’s brains are ready to think about the horse race, or ready to start parsing candidates,” said Eric Phillips, a consultant and former press secretary to de Blasio, who is unaffiliated with any of the mayoral campaigns. “The race is very open. I think it will start to whittle pretty quickly.”