David Paterson, the former Democratic governor of New York, is calling for a shakeup in the New York City mayor's race. 

Paterson wants Mayor Eric Adams and Andrew Cuomo to unite to defeat Zohran Mamdani, the Democratic nominee. He says either Adams or Cuomo should drop their independent campaign and support the other, or risk handing the election to Mamdani, a progressive and the current frontrunner. 

Former governor urges Adams or Cuomo to exit NYC mayor's race

"His policy on freezing rent is impossible. There's no way he can do that," Paterson said, referring to one of Mamdani's signature proposals. "This is a job for someone who has experience, a job for someone who can make a plan work." 

Paterson did not endorse a candidate at his news conference Monday, but said one of the leading independents should exit the race in order to prevent a split vote.

He warned that both Adams and Cuomo staying in the race could split the vote and deliver City Hall to Mamdani, a candidate who he said is unprepared to govern and has proposed unrealistic policies. 

"There are candidates running on independent lines. They're trying to get support and what I'm trying to focus on today is who would emerge from that group of people to possibly lead the city," he said.

Paterson, who governed New York from 2008-2010, called Cuomo, his three-term successor in Albany, the best choice before Mamdani won the primary, but has shifted his tone since.  

When asked how he plans to help moderates coalesce around one candidate, Paterson said the business community could step in through polling and fundraising efforts.  

"This is very unusual. We have a 33-year-old, no experience man running for mayor, versus a mayor who's had his problems, versus a former governor who just got shellacked in a Democratic primary," political consultant Hank Sheinkopf said. "How this shakes out depends entirely on the kind of campaigns people run."

Cuomo, Mamdani campaigns respond to Paterson's proposal

CBS News New York reached out to the Cuomo and Mamdani campaigns for comment on Paterson's proposal. 

"Governor Cuomo got into this race out of his deep concern for and love of this City -- the belief that we can come together and not only take these challenges head on, but that we can build a fairer, safer, more prosperous New York for all who live here, and that he is the candidate with the experience and proven record of accomplishment to get the job done. Mayor Adams did not run in the Democratic primary because he knew he was anathema to Democrats and unelectable. Nothing has changed," a Cuomo campaign spokesperson said. "We do not see any path to victory for Mayor Adams. This is the time to put aside the usual political selfishness and agree to do what is truly best for all New Yorkers. While we review this proposal, we call on other candidates to do the same."

"More than 545,000 New Yorkers voted for Zohran Mamdani, the most votes any Democratic primary candidate has received in 36 years. In the coming months, Zohran looks forward to growing this coalition and reaching new voters with his vision for an affordable New York City and his plan to deliver universal childcare, fast and free buses, and a rent-freeze for more than 2 million New Yorkers," Mamdani's campaign said. 

Political experts say it's still early in the race, and voters should expect the unexpected, especially since there's no ranked choice voting in the general election. 

"In every mayoral election of consequence, something crazy happens. Something crazy will happen, and who knows who will be elected," Sheinkopf said. 

Sheinkopf added first-term incumbent mayors have only been defeated twice in the last 60 years: Abe Beame in 1977 and David Dinkins in 1989. 

Adams takes aim at mayor's race challengers

Appearing on CNBC Monday morning, Adams took aim at both Mamdani, for his campaign promises, and Cuomo, for staying in the race. 

"For [Cuomo] to see that I was on my own independent line prior to the race and then for him to join it, he knew he was setting us up for this," the mayor said. "He created this scenario. He knew what the outcome was going be. It was the wrong thing to do. He spent $25 or $30 million. He put his message out. Voters heard it. He lost by 12 -- 12 percentage points."

Adams told CNBC that Cuomo asked him to step aside in the race. 

"I said, 'Andrew, are you that level of arrogance? I'm the sitting mayor. I'm the sitting mayor of the city of New York and you expect for me to step aside when you just lost to Zohran by 12 points?'" he said. 

The Rev. Al Sharpton urged Cuomo to abandon his mayoral campaign last week. 

"Rally behind me. I won as mayor. You know, I'm the only one that's in the race right now that has ever won as mayor," Adams said.

White House border czar on prospect of Mamdani winning mayor's race

Tom Homan, the Trump administration border czar, responded Monday to a question about Mamdani potentially not cooperating with federal immigration officials if elected mayor. 

"Good luck on that. We're going to be in New York City, and President Trump said it two weeks ago. We're going to double down, triple down on sanctuary cities. Why? Not because we're a blue city or blue state, because we know that's where the problem is. We know they're releasing public safety threats and national security threats to the streets every day, because they don't honor our detainers. We know that. We don't have that problem like in Florida, where every sheriff in the state is working with us," Homan said. "So I've said it before, we'll flood the zone of sanctuary cities ... We're going to get the bad guys. So, they don't want to help, get out of the way."