Teachers’ Union Backs Stringer for N.Y.C. Mayor, Giving Him a Boost

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.