Meanwhile, the Trump factor looms over both Mamdani’s place in midterm messaging and his success as mayor.

The president already pledged to take punitive measures against New York City should Mamdani win, as he called the state assemblyman a “communist” and offered Cuomo a last-minute endorsement. After Mamdani’s win, the White House released an image that appeared to be a New York Knicks logo containing the words “Trump Is Your President.”

Mamdani has pledged to fight Trump head-on and said in his victory speech that he would dismantle “the conditions” in New York City “that allowed” Trump “to accumulate power.”

“This is not only about how we stop Trump,” he said, “but how to stop the next one.”

A person familiar with the White House’s thinking said how much the president and his allies focus on Mamdani in the midterms depended not only on whether he won Tuesday or by how much, but also on how he ended up governing.

“I’m of the mind that it’s too early to assess how useful he is as a national foil,” this person said. “We’ll know soon.”

One key policy area to watch

Green, the co-founder of the Progressive Change Campaign Committee, said he’s particularly keen to see how Mamdani moves to bring his universal child care pledge to fruition. National Democrats have pushed for similar child care policies in recent years to no avail, as costs have soared.

“It would both debunk a talking point that it’s impossible for him to get something done on things that require Albany’s approval and also be a North Star for Democrats, if he can actually get child care to be more affordable,” Green said.

New York Gov. Kathy Hochul, a Democrat, has expressed interest in working with Mamdani on the issue. While Mamdani is set to oversee a bureaucracy that has a workforce of more than 300,000 people, his powers are somewhat limited, and he will need buy-in from the New York City Council, the state Legislature in Albany and other stakeholders to make his goals reality.

Already, Hochul has not expressed much enthusiasm for a tax hike, as Mamdani calls for a 2% tax on incomes over $1 million to fund his proposals.

Peduto said Mamdani can make progress on his agenda but needs to get corporations, local nonprofits and foundations, state leaders and the city’s congressional delegation on board to make it a reality.

“He can put together pilot programs and begin to put together different initiatives that will allow him to see success,” he said. “But only if he decides to be a consensus builder, and does not allow supporters who simply want to defeat another side control the agenda.”

As it stands, there is a Democratic divide over how much to feature Mamdani in their own midterm messaging.

Democrats who say they disagree with Mamdani do praise his focus on affordability, while progressives want to drive a contrast between Mamdani’s new vision for governance and center-left candidates who they say mostly built their campaigns around anti-Trump outrage

“Without worrying about the labels or even any one individual issue, there’s a defining choice for Democrats of — do we have just an anti-Trump message or a fresh feeling, forward looking agenda that taps into economic populism and challenges billionaires,” Green said, adding that Mamdani’s campaign “will be an ongoing symbol for Democrats.”

Sen. Ruben Gallego, D-Ariz., who has shared some political consultants with Mamdani, said his candidacy showed that candidates who talk “to the needs of the community, you’re going to have success.”

“I don’t agree with Zohran on everything, and I have different prescriptions for some of the ailments in society and the economy, but he’s talking about it,” Gallego said. “He ran against somebody who was both just corrupt to begin with, but No. 2, didn’t talk to people about what they were worried about. Voters in New York were worried about the cost of living, about having a future, and Zohran talked about that.”

“Zohran can’t win in Arizona, I can’t win in New York City,” Gallego added. “But we have very similar success in the fact that we talk to people and are trying to actually solve a problem that they feel every day.”