Winning City Hall was the easy part. The real test of Zohran Mamdani's political empire is happening right now in the voting booths of Brooklyn, Queens, and Manhattan.
Just one year after his stunning upset victory over Andrew Cuomo to become the first democratic socialist mayor of New York City, Mamdani isn't playing defense. He isn't trying to smooth things over with the Democratic establishment. Instead, he's trying to replace them. By backing a trio of hard-left primary challengers against entrenched congressional incumbents, Mamdani is testing whether his personal brand of progressive populist magic can expand beyond City Hall or if he's about to hit a very hard ceiling.
It's an insanely risky bet. If his candidates win today, he essentially remakes the city's congressional delegation in his own image, dealing a massive blow to House Minority Leader Hakeem Jeffries and Governor Kathy Hochul. If they lose, the narrative changes instantly. He goes from an unstoppable political phenomenon to a vulnerable, isolated executive who doesn't have the coattails to build a lasting movement.
The proxy wars tearing apart the city's map
Mamdani didn't just throw out a few lazy press release endorsements. He went all in. He cut television commercials that ran during high-profile Knicks playoff games, spoke at packed weekend rallies, and deployed his formidable campaign apparatus to the streets.
The biggest battleground is New York's 10th Congressional District, stretching from lower Manhattan deep into Brooklyn. Here, former City Comptroller Brad Lander is waging a fierce left-wing challenge against incumbent Representative Dan Goldman. During the 2025 mayoral race, Mamdani and Lander cross-endorsed each other in the ranked-choice voting rounds. Now, Mamdani is trying to clear Goldman out of Washington.
This race has turned incredibly bitter, specifically centered on the war in Gaza. Both Lander and Goldman are Jewish, but they represent a massive, painful generational divide. Lander has relentlessly criticized Goldman for not taking a tougher stance against Israel's actions in Gaza. Goldman, a wealthy heir to the Levi Strauss fortune who served as the lead Democratic lawyer in Donald Trump’s first impeachment trial, has the institutional backing of Jeffries and Hochul. While early polling gave Lander a slight edge, the turnout in wealthy Manhattan neighborhoods vs. progressive Brooklyn pockets will decide everything.
Further north in the 13th District, covering Upper Manhattan and parts of the Bronx, Mamdani threw a bomb into local politics by backing 32-year-old democratic socialist Darializa Avila Chevalier. She's a former field organizer for Mamdani who works at a public defender's office. She's aiming to unseat five-term incumbent Representative Adriano Espaillat.
This endorsement genuinely shocked the political establishment. Insiders whispered that Mamdani had quiet agreements to support Espaillat after Espaillat backed him following the 2025 primary. By breaking that peace, Mamdani angered the Congressional Hispanic Caucus. The race turned ugly fast. Espaillat's camp hammered Chevalier over deleted tweets from 2021 where she used explicit language to attack Kamala Harris. Chevalier apologized, but the damage was done. The campaign also devolved into toxic arguments over identity, with Chevalier accusing Espaillat's surrogates of spreading rumors that she wasn't actually of Dominican descent. Mamdani had to publicly step in to condemn the rhetoric, showing how messy this proxy war has gotten.
Then there is the 7th District, spanning western Brooklyn and Queens. With veteran Representative Nydia Velázquez retiring, the district—often called part of the local "Commie Corridor" due to its heavy leftward tilt—should have been an easy handoff. Velázquez endorsed Brooklyn Borough President Antonio Reynoso, a traditional progressive. But Mamdani refused to fall in line, backing Assemblymember Claire Valdez, a self-described democratic socialist. It's a pure ideological purity test: established progressive vs. democratic socialist insurgent.
What most people get wrong about Mamdani's strategy
Pundits keep calling this a reckless move. They think a new mayor should be hoarding political capital to pass bills through the City Council, not spending it on grueling primary fights against his own party leaders.
But they don't understand how democratic socialism operates in New York.
Mamdani knows his mayoral victory wasn't a solo achievement. It was driven by the New York City Democratic Socialists of America (DSA) and a highly organized volunteer army of young, rent-burdened voters who want radical policy changes like flat wealth taxes and permanent rent freezes. That movement naturally wants to grow. If Mamdani behaves like a typical transactional politician, his base will view him as a sellout. He needs a friendly delegation in Washington to help fund the massive public housing and transit expansions he promised.
Staying neutral wasn't an option for him. He rules by polarization. By drawing a line in the sand against moderate power brokers like Jeffries and Goldman, he keeps his base energized and organized for the structural battles ahead at City Hall.
The heavy price of a Tuesday loss
You can't ignore the immense danger here for the mayor. Governing New York City requires cutting deals with Albany and Washington. By trying to unseat Espaillat and Goldman, Mamdani has alienating the exact people who control federal funding pipelines.
If Goldman and Espaillat cruise to easy victories on Tuesday night, Mamdani's aura of invincibility vanishes. Moderate Democrats in the state legislature and the City Council will see that his endorsement can't save challengers in tough districts. They will stop fearing him. His ambitious legislative agenda—including his controversial plan to impose a 2% wealth tax on New Yorkers earning over $1 million—could stall instantly.
Voters are heading to the polls right now, and the results will define the limits of the democratic socialist movement in America's largest city. Watch the margins in lower Manhattan and the turnout numbers in Upper Manhattan. They won't just tell you who is going to Congress. They will tell you whether Zohran Mamdani actually owns New York City, or if he just borrowed it for a year.
To see how these local neighborhood dynamics are playing out on the ground right before the numbers come in, you can watch this detailed breakdown of the key primary matchups which highlights exactly where each candidate is hunting for votes in the final hours.
