The 33-year-old democratic socialist would be the first Muslim to lead the nation's largest city if elected.
The primary in staunchly liberal New York is likely to determine who becomes mayor in November's election.
The former governor's loss marks the "biggest upset in modern NYC history," Trip Yang, a political strategist, told the BBC.
"A massive win for Zohran Mamdani that shows that when Donald Trump is President, New York Democrats want to see their leaders fight with enthusiasm and courage, and that's what Zohran showed voters."
In an interview with the New York Times, Cuomo said he was still examining whether he would run in the general election in November on the independent line.
THANK YOU! Finally someone with some sense. I feel like I've been taking crazy pills.
This should not be "stunning" anyone. Cuomo is a creepy old man, Zohran is an equal but opposite reaction to Trump -- and the one that NYC needs.
So many major news outlets are busy kissing Trump and establishment Dems' asses because they have become dependent on the same wealthy donors that prop them up. I'm really worried for the future when I see this headline over and over "SHOCK" ... What's shocking is how all of these media companies have their head so far up their ass. I really hope this encourages them to get their shit together and report what you see, not what they think rich people want to hear.
I no longer trust any polls. Feel free to try to convince me otherwise, but in my experience (anecdotal, I know) they have been wrong in many cases. Further, I think they can do more harm than good. For example, if a poll suggests a given candidate will likely win easily, it could -- and I would argue -- does discourage voters from going out of their way to cast their ballot. Sidebar: Voting in the US doesn't have to be so fucking hard. Election days -- especially in November -- should be a holiday.