Andrew Cuomo has conceded in the New York City mayoral Democratic primary to state assemblyman Zohran Mamdani in a stunning political upset.

Cuomo, the state's former governor, was attempting to pull off a political comeback after resigning from office in 2021 amid a sexual harassment scandal.

In a speech to supporters, Cuomo said Mamdani - a 33-year-old democratic socialist - had "won" the primary race and that "we are going to take a look and make some decisions".

"Tonight is his night," Cuomo said. If elected, Mamdani would be the first Muslim and Indian American to lead the nation's largest city.

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