Zohran Mamdani's surge to the top in New York City's Democratic mayoral primary came with the help of an army of volunteers who set a goal of knocking on 1 million doors to get votes.

The hotel workers' union and the building service workers' union represent more than 120,000 people in New York City.

President Donald Trump on Sunday issued a warning for New York city mayoral candidate Zohran Mamdani, the presumptive Democratic nominee who defeated former Governor Andrew Cuomo in last week's primary and sent shockwaves throughout the national political establishment.