New York Mayor Zohran Mamdani is seeking to reshape the city's congressional delegation by endorsing three candidates challenging incumbent Democratic lawmakers, a move that could expand his democratic socialist movement's power or potentially set it back. The mayor has backed former NYC Comptroller Brad Lander against Rep. Dan Goldman in a Manhattan-Brooklyn district, state Assemblywoman Claire Valdez against Brooklyn Borough President Antonio Reynoso in a Brooklyn-Queens seat, and activist Darializa Avila Chevalier against Rep. Adriano Espaillat, chairman of the Congressional Hispanic Caucus, in a Bronx-Manhattan district.

The three candidates appeared alongside Mamdani in an advertisement that ran following Game 1 of the NBA Finals between the New York Knicks and San Antonio Spurs. "New York, we know anything is possible with a great team," Mamdani said before introducing each endorsee. "Get out and vote, this is the team. This is our year."

What the Left Is Saying

Supporters of Mamdani's endorsements describe them as a strategic effort to build on his 2025 mayoral victory and shape the next generation of Democratic leadership in New York. Rebecca Katz, a prominent Democratic strategist whose firm worked with Mamdani during his mayoral run, said the approach carries both risk and potential reward. "This is high-risk, high-reward," Katz told NBC News. "He's not afraid to take some big swings."

A Democratic strategist working on behalf of Mamdani's preferred candidates argued the timing makes political sense for the mayor. "He may as well take his shots as they present themselves, shaping the next generation of leadership here in New York," this person said, speaking on condition of anonymity. "This cycle he is at the peak of his political popularity where across the city he is broadly popular. An endorsement from him has the potential to be difference making."

Valdez, a 36-year-old Latina and Native American who moved to the city in 2015, said the mayor's endorsement has been significant given his popularity in her district. "We’re all very supportive of the mayor in his race last year," she said in an interview. "I see this as kind of like the continuation of this movement that won his race last year."

Avila Chevalier expressed pride in receiving Mamdani's backing, calling it evidence her campaign has built a serious challenge. At a press conference in Harlem, she addressed questions about her district by saying: "Here's what the establishment never understood about Uptown and the Bronx. We don't wait for permission."

What the Right Is Saying

Critics of Mamdani's approach argue the endorsements prioritize ideological purity over effective governance and could damage his relationships with federal officials who control city funding. Bradley Tusk, a top adviser to former Mayor Michael Bloomberg, offered a sharp assessment: "For Mamdani, the actual governing of New York City and the well-being of the people he represents comes a distant second to his political movement and his status as its leader."

Tusk added that losing political capital in these races would have consequences for constituents. "If he loses political capital that hurts his ability to deliver for his constituents, that's far less important to him than anointing candidates who are sufficiently pure to meet his standards," Tusk said.

The incumbent lawmakers targeted by Mamdani's endorsements expressed respect for his decisions but voiced concern about potential impacts on federal-city relations. Espaillat, who won his seat in 2016 after two near-miss runs as an anti-incumbent challenger himself, declined to elaborate on reports that Mamdani went back on a private commitment to support him. "That's his decision. We respect it," Espaillat said. "I got my decision... We're campaigning, and we're going to win." The congressman added: "It's important for all executives, from mayors to governors, to have good relationships with the federal government. I mean, their budgets depend very strongly on what we do here."

Goldman downplayed Mamdani's endorsement but noted he had worked with the mayor on issues including the Brooklyn Marine Terminal waterfront redevelopment project. "I've had a good working relationship with the mayor and his office," Goldman said. When asked if the endorsement makes it harder to work together, he replied: "I am a professional, and I do the work, and the campaign-related stuff is separate."

Retiring Rep. Nydia Velázquez, who chose Reynoso as her preferred successor, emphasized the importance of maintaining federal partnerships. "This is America. Everyone has the right to do whatever they want," she said. "You need to keep your doors open to work with everyone, especially when the federal government plays such an important role."

What the Numbers Show

Mamdani won the mayoral race in November against former Gov. Andrew Cuomo by routing him in all three of the districts where these congressional contests are taking place — Manhattan's 12th District (Goldman's seat), Brooklyn-Queens' 7th District (Velázquez's retiring seat), and the Bronx-Manhattan's 13th District (Espaillat's seat).

The three races are among the most closely watched primary contests in New York this cycle. In two of the races — Velázquez's open 7th District and Espaillat's 13th District — Mamdani has endorsed candidates in their 30s, part of what his supporters describe as a push for generational change.

A Democratic strategist working on behalf of one of the incumbents said the mayor's endorsement carries significant weight. "That's all Claire Valdez has," this person said of the mayor's backing. "If she did not have the mayor's endorsement, it would not be like a particularly close race."

The Israeli-Palestinian conflict has emerged as a central issue in each contest, with questions about whether candidates describe Israel's conduct in Gaza as genocide and their positions on donations from groups associated with AIPAC playing prominent roles in the races.

The Bottom Line

Mamdani's endorsements represent his most aggressive political moves yet as mayor, testing whether his popularity can translate into success for candidates who align more closely with his democratic socialist platform. The outcomes could either strengthen his movement's influence in Washington or expose limits to his political reach.

The races will also serve as a referendum on whether progressive challengers can defeat established Democratic incumbents in New York, and whether Mamdani's willingness to back away from private political agreements affects his ability to work with federal officials who control significant city funding. The three primary elections are expected to draw heightened attention given their potential implications for the broader direction of New York's Democratic Party.