The two rivals were joined on stage by Republican Curtis Sliwa weeks ahead of the multi-way general election to lead the nation's largest city.

Andrew Cuomo and Zohran Mamdani both opened Thursday’s New York mayoral debate by saying a future headline about their first year in office would celebrate lowering costs for New Yorkers.

The next 50 minutes of the debate — aired on NBC New York and Telemundo New York, in partnership with Politico — turned into an all-out brawl over issues including crime, the war in Gaza and President Donald Trump as the candidates tore into one another in deeply personal ways.

During one back-and-forth focused on which candidate has the right experience for the job, Mamdani, a state assemblyman, blasted Cuomo, the former governor, for his handling of nursing homes during the Covid pandemic. Cuomo, who resigned from office amid allegations of sexual harassment, which he denies, had just said the mayorship was “no job for on-the-job training.”

Mamdani said: “What I don’t have in experience, I make up for in integrity. And what you don’t have in integrity, you could never make up for in experience.”

Mamdani, the Democratic nominee, and Cuomo, running as an independent after losing the Democratic primary in June, were joined onstage by Republican nominee Curtis Sliwa, with the three clashing over how to handle the police department and mental health calls, the education system, taxes and the business climate in New York City.

Mamdani, a self-described Democratic socialist, enters the stretch run of the election with a commanding lead, though Cuomo has closed some ground since Mayor Eric Adams dropped out of the contest.

Trump has sought to influence the outcome of the race and has repeatedly threatened to withhold federal funding from New York should Mamdani win the contest next month. And the president’s influence in New York was a central discussion of the debate.

Each candidate was asked when he had last spoken with Trump, with Cuomo saying he believed it was after the attempt on Trump’s life in Pennsylvania last year. Sliwa said it had been many years, while Mamdani said he never has never spoken to Trump.

But Mamdani did express willingness to work with Trump to lower costs — before he attacked Cuomo over reports that he had discussed the race with Trump.

“I don’t need the president’s assistance,” Mamdani said. “And what I’d tell the president is if he ever wants to come for New Yorkers in the way that he has been, he’s going to have to get through me as the next mayor of the city.”

Cuomo said he never had such a conversation with Trump and talked up past “bloody battles” with him during Covid.

“I’d like to avoid them,” Cuomo said.

Following the debate, NBC News asked Mamdani what he would say to New Yorkers concerned that Trump will follow through on threats to punish the city by withholding additional federal funding should the state assemblyman win next month.

“I think what we’re seeing right now is that Donald Trump is making a threat every day that he wakes up,” Mamdani said. “He’s making a threat to suspend funding to the city, like the $18 billion in infrastructure grants he’s already made good on, threats to suspend more than $50 million because we refuse to give up our trans students, or $80 million because we actually wanted to take care of every person in the city, regardless of their status. I would actually fight each of those threats, not treat them as law because they come out of his mouth.”

He pointed to legal battles in California, saying that “for every dollar they spent on legal fees, they retrieved more than $30,000 in federal funds that would have been stripped of them.”

Approached by NBC News minutes earlier, Cuomo was emphatic when asked if the president would move forward with his threats no matter who wins next month.

“No,” Cuomo said. “No!”

During the debate, Mamdani also attacked Cuomo for not taking a strong enough line in defending state Attorney General Letitia James, who was recently indicted on federal charges after Trump had called for her prosecution.

“I said political weaponization of the justice system is wrong,” Cuomo said. “Both sides do it. It’s wrong when Donald Trump does it. It’s wrong when they did it to [James] Comey. It’s wrong when Comey did it to Hillary” Clinton.

Sliwa cut in and said New Yorkers will suffer if either Cuomo or Mamdani takes on Trump.

“Look, you can be tough, but you can’t be tough if it’s going to cost people desperately needed federal funds,” Sliwa said. “Zohran Mamdani, the president has already said it’s going to take $7 billion out of the budget right from the start if you’re elected mayor. People are going to suffer in this city, people who need those federal funds. What I would do is sit and negotiate.”

While Sliwa sought his openings in the debate, Mamdani and Cuomo were the main event, often ignoring his jibes — except to agree when he was attacking the other candidate.

Democratic divides

Meanwhile, Mamdani and Cuomo battled over who is a real Democrat, too. Mamdani said voters who believe there is no difference between the Democratic and Republican parties should vote for Cuomo, while voters who want a mayor to stand up to Trump and his donors should back him.

Cuomo then said Mamdani isn’t a Democrat, focusing on his membership in the Democratic Socialists of America, and accused him of not voting for Kamala Harris last fall. (Mamdani said voters should leave their presidential primary ballots blank if they disagreed with then-President Joe Biden’s handling of the war in Gaza.)

“If you want to look for me on the ballot, you’ll find me as the Democrat,” Mamdani said.

The war in Gaza took up a significant part of the debate. Mamdani has accused Israel of carrying out a “genocide” and in a Fox News interview Wednesday, he declined to say whether Hamas should forfeit its weapons following the recent ceasefire agreement.

“Of course I believe that they should lay down their arms. I’m proud to be one of the first elected officials in the state who called for a ceasefire, and calling for a ceasefire means ceasing fire,” he said. “That means all parties have to cease fire and put down their weapons.

“And the reason that we call for that is not only for the end of the genocide, but also an unimpeded access of humanitarian aid,” Mamdani said. “I, like many New Yorkers, am hopeful that this ceasefire will hold.”

Cuomo responded that Mamdani is refusing to “denounce Hamas” and separately said he was speaking in “code” with his answer — and that code signaled that Israel “does not have a right to exist as a Jewish state.” Mamdani responded that Cuomo was acting as Israeli Prime Minister Benjamin Netanyahu’s “legal defense team during the course of this genocide.”

He added that conversations with Jewish New Yorkers had led him to discourage using the phrase “globalize the intifada,” a phrase he said he does not use.

“And what I’m looking to do as the first Muslim mayor of this city is to ensure that we bring every New Yorker together, Jewish New Yorkers, Muslim New Yorkers, every single person that calls the city home. They understand they won’t just be protected, but they will belong,” he said.

Cuomo attacked Mamdani for not explicitly denouncing the phrase.

“He is a divisive personality across the board,” Cuomo said.

Handling crime and costs

On crime, Mamdani said he had spoken to police officers to apologize for past anti-police postings, and he said he is not running on those ideas, attacking Cuomo for not focusing on his actual plans. Cuomo said that Mamdani “doesn’t like the police” and “that’s why he won’t hire more police.”

“When everyone else says we need more police,” Cuomo said, “he wants to use social workers on domestic violence calls, which are very dangerous, and he’s told you what he thinks. He thinks the police are racist, wicked, corrupt and a threat to public safety.”

Mamdani said that as a state assemblyman, he learned “that to deliver justice means to also deliver safety, and that means leading a city where you recognize the bravery of the men and women who join the NYPD and put their lives on the line.”

“It means representing the Muslims who were illegally surveilled in my district and the Black and brown New Yorkers who have been victims of police brutality,” he said.

The second half of the debate featured more discussion about the cost of living and affordability. Each candidate was asked what he paid in groceries and rent: $2,300 for Mamdani, $3,900 for Sliwa and $7,800 for Cuomo.

Cuomo was deeply critical of Mamdani’s plans for affordable housing and free bus service, while he talked up his own experience as governor and secretary of Housing and Urban Development.

Mamdani said: “I just have to say it’s been an hour and 20 minutes of this debate, and we haven’t heard Gov. Cuomo say the word ‘affordability.’ That’s why he lost the primary.”

Mamdani criticized Cuomo for having the support of billionaire hedge fund executive Bill Ackman, to which Cuomo said, “There are a lot of New Yorkers who support me, and there are a lot of Jewish New Yorkers who support me because they think you’re antisemitic.

“So it’s not about Trump or Republicans,” Cuomo said. “It’s about you.”

The two candidates did have one point of agreement when they were asked to identify the best-ever mayor of New York City. Both shouted out Fiorello LaGuardia.

“We agree,” Mamdani said.