It comes a day after Andrew Cuomo officially announced he is staying in the race as an independent.
"What use is it to go through months of contract negotiation to win those hard-earned raises only for you to go back to your rent-stabilized apartment and face an even bigger increase in your rent?" Mamdani said.
For Mamdani, there is no bigger prize than the endorsement of DC37, the city's largest municipal labor union.
"What use is it to have the greatest city in the world if New Yorkers can't afford to live here? We do not want this to become a museum where working people once lived," Mamdani said. "We want it to be a living, breathing testament of what's possible."
Affordability is the centerpiece of Mamdani's upbeat, upstart campaign. He's already endorsed by the city's teachers' union, the Hotel Trades Council, the New York State Nurses Association, SEIU 32BJ and the New York City Central Labor Council.
On Monday, former Governor Andrew Cuomo re-launched his campaign on social media, in an upbeat, Mandani-style video. He now admits he never took his Democratic socialist opponent seriously.
"I never really debunked his proposals because I just didn't engage. That was a mistake," he told New York Magazine. "This is a crossroad for New York... and I think Mamdani takes us in exactly the wrong direction."
Asked about the mayor's race, on Tuesday, President Donald Trump, again, incorrectly described Mamdani as a "Communist" and suggested that Cuomo should stay in the race.
"I think Andrew would have a good chance at winning," Trump said. "He's got to run a tough campaign. You know, he's running against a Communist. I would think he would have a good shot at winning."
Mamdani met with several of the city's top business leaders on Tuesday. Whether he is willing or able to reassure New York's power brokers and establishment politicians is one of the biggest questions in the campaign.
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