The endorsement comes at a critical time for the city comptroller, who has struggled to gain traction in the race.
New York City’s influential teachers’ union endorsed the city comptroller, Scott M. Stringer, in the race for mayor on Monday, providing a much-needed boost to a campaign that has struggled to gain momentum thus far, despite Mr. Stringer’s deep experience in city politics.
Mr. Stringer is a decades-long ally of the United Federation of Teachers and was long considered the front-runner for its support. With nine weeks before the June 22 primary, the endorsement comes at a critical time: In the limited public polling available, Mr. Stringer consistently trails the former presidential candidate Andrew Yang and the Brooklyn borough president, Eric Adams.
In recent weeks, some labor leaders, political operatives and his own allies had privately worried about Mr. Stringer’s viability in the race, as the more moderate Mr. Yang has threatened his Manhattan base, and left-wing activists and leaders — expected to be solidly in Mr. Stringer’s corner — have not yet coalesced around a single candidate.
Mr. Stringer is hoping to assemble a broad coalition that includes both traditional sources of Democratic power — in particular, union support — as well as backing from the left-wing activist slice of the party that has been influential in several recent elections across the city. Last week, in an effort to build a unified progressive front, the Working Families Party endorsed Mr. Stringer as the party’s first choice, followed by Dianne Morales, a former nonprofit executive, and Maya Wiley, a former counsel to Mayor Bill de Blasio.
Mr. Stringer referenced his position in the race during a news conference to announce the endorsement on Monday. “This race is getting started,” he said. “I’ve been known to close strong, this union closes strong, and I promise you the race of your lifetime.”
The U.F.T.’s endorsement is coveted, because of the union’s political influence and its ability to mobilize its roughly 200,000 members. Still, its members are split into several political caucuses and may not vote as a bloc, and the union does not have the same organizational prowess as other large city unions.
Over the last year, the teachers’ union was at odds with elements of the city’s push to reopen schools in the nation’s largest school system during the pandemic, placing the U.F.T. under an unusual level of scrutiny. Some parents who were not politically active before the reopening debate became deeply frustrated by the pace of reopening and critical of the union.
It is not at all clear whether there are enough parents who have turned against the union to actually make a difference in the upcoming election; the vast majority of city parents have kept their children learning from home this year, and most city parents do not play close attention to union politics.
The city has now reopened all grades for in-person learning, with many younger students back full-time, though some high school students who have returned to classrooms are still learning online from inside their school buildings.
Mr. Stringer, who is himself a public school parent, was not a vocal supporter of Mr. de Blasio’s push to bring students back into classrooms last fall and was sometimes sharply critical of the mayor’s effort. Mr. Stringer and his wife decided to send one of their sons back into classrooms last fall and keep their other son learning remotely.
As comptroller, Mr. Stringer has also criticized the mayor’s handling of the city’s homeless student crisis, and appeared to briefly jeopardize the rollout of the successful universal prekindergarten program after he raised alarms about the contracting process for some of those programs.
Mr. Stringer’s promise to put two teachers in every elementary school classroom as mayor is attractive to the union, since it would boost its membership. But the idea has also appealed to education experts who have said adding more teachers could make traditional public schools more attractive to parents who might have considered gifted and talented programs or private schools, which tend to have large teaching staffs.
Mr. Stringer is also one of a small group of mayoral hopefuls who have committed to eliminating the high-stakes exam that dictates entry into the city’s top high schools, including Stuyvesant High School. Like many of his rivals, he is skeptical about charter schools, a position that is all but a prerequisite for the U.F.T.’s backing.
Mr. Stringer’s campaign is likely to use the endorsement as fresh evidence that his coalition-building strategy remains viable. Perhaps more than any other candidate in the race, Mr. Stringer’s candidacy — already supported by a long list of prominent New Yorkers — will test whether endorsements move voters in an unpredictable election unfolding amid a pandemic.
The U.F.T.’s choice of Mr. Stringer also carries enormous stakes for the union.
Unlike other powerful city unions, the teachers union has failed to endorse a winning candidate since 1989, when it backed the former mayor David N. Dinkins. That has prompted concern among U.F.T. officials that the union’s clout in electoral politics could shrink if it again bets on the wrong candidate.
The former mayor Michael R. Bloomberg, who clashed with the U.F.T. throughout his tenure, went so far as to call the union’s endorsement “the kiss of death” during the 2013 race to replace him.
“I don’t know what goes through voters’ minds, but maybe they understand if the U.F.T. wants it, it ain’t good and you don’t want that person,” Mr. Bloomberg said at the time.
The outcome of the race could offer major clues about how much weight the U.F.T.’s endorsement — or the backing of any municipal union — still matters in local politics.
With the U.F.T. endorsement settled, most major municipal unions have made their choices — with the notable exception of the union representing transit workers. Many prominent unions have backed Mr. Adams, but Ms. Wiley scored a major victory in February when she won the endorsement of Local 1199 of the Service Employees International Union, the city’s largest union.
In some years, labor unions have largely flocked to a particular candidate. Mr. Stringer, for example, had overwhelming support from labor groups in his 2013 race for comptroller, when he defeated the former governor, Eliot Spitzer. But this year, the labor endorsements are diffuse.
One of the biggest open questions in the mayoral race is whether there will be any union-affiliated independent expenditure effort to stop Mr. Yang — but it is not yet clear which organizations, if any, would have both the resources and the inclination to mount one.
Mr. Stringer has won the backing of other education unions, including the union representing school principals and administrators, and the union representing teachers and staff at the City University of New York. Mr. Yang has not earned a major union endorsement yet, but is leading in all publicly available polling.
The teachers’ union membership includes about 75,000 active classroom teachers — as well as roughly 64,000 retirees, many of whom no longer live in New York. About 90 percent of the U.F.T.’s delegate assembly — a group of about 3,400 elected representatives, including educators from each school in the city — voted to back Mr. Stringer on Monday afternoon.
The union has, for decades, played a major and occasionally decisive role in key education decisions, and that has been particularly true over the last year.
The U.F.T. made a number of safety demands last summer, and tensions escalated to the point that the union president, Michael Mulgrew, suggested that teachers would strike if those safety demands were not met. Public health experts supported many of those demands, such as improved ventilation, but some families were angered by the union’s insistence that all rules remain in place even as teachers were vaccinated.
Advisers for Mr. Yang are hoping to attract at least some of those disaffected families.
During a recent interview on Fox Business, Bradley Tusk, the powerful political strategist and lobbyist who is, with his team, managing Mr. Yang’s campaign, said his candidate “takes positions that are a little at odds with the Democratic orthodoxy on things like education.
“The teachers’ unions [have] blocked the ability for students to come back into the schools of New York City,” he added.
Though Mr. Yang accused the union of delaying school reopening in an interview with Politico, he walked back his comments during a recent U.F.T. forum held to determine the endorsement. Mr. Yang said he and Mr. Mulgrew had agreed that the mayor, not the union, was primarily to blame for any stumbles on reopening. City Hall officials say that last summer, the union represented a significant obstacle to reopening.
Dana Rubinstein contributed reporting.