After stunning NYC mayor primary upset, Mamdani tells ABC News Democrats need to focus on economic agenda

New York state assemblyman Zohran Mamdani, speaking with ABC News the day after achieving an upset in the New York City Democratic mayoral primary, said that he believes his strategy that focused on affordability and economics could be a blueprint for Democrats across the country.

"I think there's a question of how we return back to what made so many of us proud to be Democrats," Mamdani told ABC News Senior Political Correspondent Rachel Scott in an interview on Wednesday.

Watch more of Rachel Scott's broadcast interview with Zohran Mamdani on "Good Morning America" Thursday at 7 a.m. ET.

"How do you do that?" Scott asked.

"I think it's that focus on an economic agenda, on ensuring that people can do more than just struggle," Mamdani replied.

The self-described Democratic Socialist declared victory over former Gov. Andrew Cuomo as results rolled in for the closely watched primary Tuesday night. Cuomo conceded in the primary, saying "Tonight is [Mamdani's] night. He deserved it," but he said he has not ruled out running as an independent in the general election.

Mamdani also responded to a barb from President Donald Trump, who called Mamdani "a 100% Communist Lunatic" in a post on his social media platform on Wednesday afternoon.

Trump wrote, "It's finally happened, the Democrats have crossed the line. Zohran Mamdani, a 100% Communist Lunatic, has just won the Dem Primary, and is on his way to becoming Mayor. We've had Radical Lefties before, but this is getting a little ridiculous."

"What do you say to that?" Scott asked Mamdani.

"You know, this is not the first time that President Trump is going to comment on myself, and I encourage him -- just like I encourage every New Yorker -- to learn about my actual policies to make the city affordable," Mamdani said.

He added that Trump had run a presidential campaign that in part focused on making groceries and the cost of living cheaper, although he criticized the president as "uninterested and unable to deliver on that."

Mamdani added, "If that is ever something he changes his mind on, then that's somewhere that I would be willing to work with him."

But he said he would challenge Trump on the president's deportation policies and immigration crackdown: "But if he continues to focus on persecuting political enemies and on trying to detain and disappear New Yorkers, be it on the basis of their documentation or their sexual orientation or their politics, that is someone that I will fight time and again."

The White House has defended its deportation goals and methods as cracking down on undocumented migrants who have committed crimes.

Mamdani had focused his campaign on a progressive, economy-focused platform that included a rent freeze for rent-stabilized apartments and eliminating fares for New York City buses.

Mamdani will face incumbent Mayor Eric Adams, who is running as an independent, and Curtis Sliwa, the only Republican candidate in the race. Mamdani would be the city's first Muslim mayor and its youngest in a century if elected.

ABC News' Brittany Shepherd contributed to this report.