Assemblyman Zohran Mamdani’s campaign for New York City mayor is surging — to within striking distance of the Democratic frontrunner, Governor Cuomo, after being a no-name candidate in a crowded field — and a night at a Democratic Socialists of America debate watch party makes clear why.

A bar near City Hall Park was packed with roughly 200 Mamdani supporters when I arrived just in time to see the candidates give their opening statements. Mr. Mamdani started with his signature “affordability” tagline, listing his promises of free childcare and a rent freeze.

“And before you ask, I’ll pay for it by taxing the rich,” Mr. Mamdani said.

The bar crowd erupted in cheers, drowning out the rest of the candidate’s remarks. Mr. Cuomo’s opening statement came next, though it was impossible to hear over the boos.

The Democratic mayoral primary has become a two-person race between Messrs. Mamdani and Cuomo — with the city comptroller, Brad Lander, in a distant third place. Most polls show Mr. Cuomo winning by more than 10 points after multiple rounds of ranked choice voting. The former Empire State governor’s margin of victory, though, keeps shrinking.

A Data for Progress survey from early June, commissioned by a Mamdani-aligned super PAC, found Mr. Cuomo winning in the eighth round by only two points. The poll is an outlier, but the bottom line, according to strategists who spoke to The New York Sun, is that turnout will be critical. Early voting starts on Saturday. The election is June 24.

The Democratic Socialists of America sent me multiple email messages after I confirmed I’d be at the debate watch party, asking for friends’ email addresses and whether I wanted to volunteer. Inside the bar, the vibe was more a social scene than a political rally. That was its brilliance. It was the place to be.

The drinks flowed freely. Some in the crowd donned office attire, but most wore T-shirts, some with slogans like “Tax The Rich” or “Don’t Rank Cuomo.” The average age appeared to be roughly 32. The bar felt like a five- or 10-year reunion for Oberlin College.

Polls show Mr. Mamdani’s base of support is white, college-educated, under 45, and living at Brooklyn or Manhattan. While Mr. Mamdani and his DSA supporters fashion themselves as defenders of the working class, Mr. Cuomo was quick to point out in Thursday night’s debate that he has more union endorsements than any other candidate.

The debate got personal. Mr. Lander landed the toughest blows at Mr. Cuomo, but all the candidates piled on the frontrunner, except for businessman Whitney Tilson. Mr. Lander pointed to a man in the audience, Peter Arbeeny, who lost his father to Covid in a nursing home, and asked Mr. Cuomo if he would apologize for requiring nursing homes to accept Covid-positive patients during the pandemic. 

Mr. Lander also attacked Mr. Cuomo for the sexual harassment scandals that forced him to resign from the governorship. Mr. Lander earned the top mayoral pick from a panel convened by the New York Times opinion section Thursday morning. 

Mr. Mamdani attacked Mr. Cuomo as corrupt and not a real New Yorker. Mr. Cuomo defined voting for Mr. Mamdani as “reckless and dangerous,” noting that the Democratic Socialist has only passed three bills in his time in the state assembly and has “never held a real job.”

“I think inexperience is dangerous,” Mr. Cuomo said. “And now you have Donald Trump on top of all of that.”

“I’ve never had to resign in disgrace. I have never cut Medicaid. I have never stolen hundreds of millions of dollars from the MTA,” Mr. Mamdani responded, with some heat. “I have never hounded the 13 women who credibly accused me of sexual harassment. I have never sued for their gynecological records.”

The debate questions on antisemitism drew grunts and boos inside the bar. A Muslim who is critical of Israel, Mr. Mamdani has struggled to define himself as not antisemitic while also being critical of the Jewish state and saying he is proud of his endorsement by the Democratic Socialists of America. The DSA is explicitly anti-Zionist, and a faction posted to X earlier this month calling for the killer of two Israeli embassy workers in Washington, D.C., to be freed.

On Thursday night, Mr. Mamdani tried to reassure Jewish New Yorkers, who make up roughly 15 percent of the Democratic primary electorate. He called October 7 a “horrific war crime,” though he also called Israel’s actions in Gaza “cruel.”

“I will protect Jewish New Yorkers and deliver them that safety,” Mr. Mamdani said, and then tried to downplay the issue entirely. “And in the words of Ed Koch, if you agree with me on nine out of 12 issues, vote for me. Twelve out of 12, see a psychiatrist.”

Mr. Cuomo wasn’t buying it: “I’m not Mr. Mamdani, I’m not antisemitic, I’m not divisive. I didn’t say I would boycott Israel.”

A former city comptroller, Scott Stringer, made his position on Israel and antisemitism clear. “I am not confused about what I believe in or who I am. I am a Zionist. I believe in the Jewish state of Israel. I’m against BDS — it’s antisemitic,” he said.

A group in the bar booed. A woman next to me laughed when Mr. Stringer mentioned that his wife works at the Jewish Heritage Museum. “Ugh, not his wife again,” she said.

Mr. Tilson also got boos for saying, “I want to be the mayor who ends the chaos, not globalizes the intifada.”

Most of the people I spoke with at the watch party said they planned to rank Mr. Lander second or third, after Mr. Mamdani, though they weren’t sure about the rest of the slate. The no. 1 point they all made was “don’t rank Cuomo.” When I mentioned that I was a reporter, every person I talked to refused to speak.

A man outside the bar later told me a DSA organizer announced before the debate started that no one should speak with reporters. Instead, they should find an official DSA representative and the representative would make a statement. When I asked for one of these representatives, a DSA member asked for my name. Then he walked back into the bar.

A few minutes later, a rotund woman in a crop top and Zohran pin came outside. “No one is available to speak to you,” she said.

“So you googled me,” I said.

“We just don’t want to speak with you,” she said.

For a party that criticizes President Trump for attacking the press as the enemy and mocks Mr. Cuomo for not taking reporters’ questions often enough, the DSA sure employed similar tactics. 

After two hours with the DSA, I realized that even if the vibe and garb of watch party attendees appears to be radical, their behavior suggests compliance to their socialist leaders. The question now is whether these young self-declared socialists will be as good at following orders when it’s not a bar party — and by that I mean voting.