Mamdani Wins Backing of Major Health Care Union That Had Endorsed Cuomo

Assemblyman Zohran Mamdani, the upstart democratic socialist who convincingly won the Democratic primary for mayor of New York City, was endorsed on Friday by the city’s powerful health care union, Local 1199 of the Service Employees International Union.

Since his win last month, Mr. Mamdani has quickly coalesced much of the city’s organized labor behind him, receiving endorsements from unions representing millions of teachers, hotel workers and nurses, among other professions.

Many of these unions, including Local 1199, had endorsed former Gov. Andrew M. Cuomo, who is now running in the general election as a third-party candidate.

The health care union’s initial support of Mr. Cuomo was seen as a sign of the longtime alliance between the former governor and the union’s former leader, George Gresham. The two had a tight relationship going back to Mr. Cuomo’s time in office, when he influenced state policies to aide Mr. Gresham and his members.

But with Mr. Gresham voted out of office this spring, the union’s executive board voted on Friday to endorse Mr. Mamdani, with the union’s recently elected president, Yvonne Armstrong, lauding Mr. Mamdani’s “plan to ensure frontline caregivers can continue working and living in our city.”

“Working people across New York City are uniting to defend our neighborhoods and our city from unprecedented attacks from extremist politicians and their billionaire donors who are taking away health care, ripping families apart and endangering our democracy,” Ms. Armstrong added in a statement.