Young self-declared socialist Zohran Mamdani was on the cusp of a stunning victory Wednesday in New York City's Democratic mayoral primary — pummeling his scandal-scarred establishment rival in a race seen as a fight for the future of the Democratic Party.

Results were not yet final. But Mamdani — who is just 33 and would become the city's first Muslim mayor — had such a commanding lead that his biggest rival, former New York Gov. Andrew Cuomo, conceded defeat overnight.

Mamdani's success was seen as a rebuke to Democratic centrists who backed the powerful Cuomo, as the party flails nationally in search of a way to counter Republican President Donald Trump's hard-right movement.