Next week’s primaries in New York will test Zohran Mamdani’s political power six months into his mayoral term and set up what’s likely to be one of the fall’s most competitive House races in the Hudson Valley. 

Mamdani has endorsed a trio of Democratic candidates running for House seats across New York City, including two who are challenging incumbents in primaries: Brad Lander, the former city comptroller who is running against Rep. Dan Goldman in the 10th District, and organizer Darializa Avila Chevalier, who is taking on Rep. Adriano Espaillat, the chair of the Congressional Hispanic Caucus, in the 13th District.

Mamdani is also backing state Assemblywoman Claire Valdez, who is locked in a close Democratic race with Brooklyn Borough President Antonio Reynoso for the 7th District seat Democrat Nydia M. Velázquez is vacating. 

All three Mamdani-backed candidates are running to the left of their opponents, who identify as progressives themselves. Espaillat and Goldman are both members of the Congressional Progressive Caucus. Avila Chevalier and Valdez are both endorsed by the New York City chapter of the Democratic Socialists of America.

While Lander’s challenge to Goldman has appeared strong for much of the year, landing the incumbent on CQ Roll Call’s list of most vulnerable House incumbents last month, Avila Chevalier’s campaign got a high-profile boost late last month when Mamdani officially endorsed her. 

In contrast, Espaillat has most of the party establishment behind him. House Minority Leader Hakeem Jeffries campaigned with the congressman last weekend, along with members of the Congressional Black Caucus.

A fourth high-profile Democratic primary for an open seat in New York City is in the 12th District currently held by retiring Rep. Jerrold Nadler. The race has drawn a crowded field of candidates, with four garnering the most attention: state Assemblymen Micah Lasher and Alex Bores; Jack Schlossberg, a social media influencer and grandson of former President John F. Kennedy; and George Conway, a Republican lawyer turned Trump critic. 

Early polls showed Schlossberg leading, but recent surveys have shown either Lasher or Bores leading the pack.  

The primary has also seen fighting between groups tied to the artificial intelligence industry, as Bores, who in the state Assembly sponsored legislation meant to safeguard the technology, has drawn significant spending for and against his campaign. 

Beyond New York City

GOP Rep. Mike Lawler is likely to face the toughest fight of his political career this fall in the battleground 17th District. He’s a top target for House Democrats, who see his Hudson Valley district — a rare Republican-held seat that Kamala Harris carried in 2024 — as one of their best pickup opportunities. 

Five Democrats are on the ballot Tuesday, but Army veteran Cait Conley and Rockland County legislator Beth Davidson are the presumed front-runners. 

Conley, the Democratic fundraising leader, has also been the beneficiary of spending by outside groups, including the New Democrat Majority, VoteVets and AFT Solidarity. But a newly formed outside group called Progressive Champions PAC, which is allegedly tied to Republicans though it hasn’t yet had to disclose its donors, spent $1.5 million on ads opposing Conley. 

“When I see Mike Lawler and MAGA Republicans lying about me, I know they’re scared,” Conley said in a closing ad released this week. “MAGA knows I will beat Mike Lawler and stop Donald Trump.” 

Lawler, a strong fundraiser, reported a $4.3 million war chest earlier this month.

The biggest contest for Republicans on Tuesday is further upstate, in the 21st District, where Rep. Elise Stefanik isn’t seeking reelection. Anthony Constatino, who won President Donald Trump’s coveted endorsement, faces state Assemblyman Robert Smullen, who is endorsed by the state Republican Party and the Conservative Party of New York State. 

The winner is expected to face Democratic dairy farmer Blake Gendebien, who started running last year when Stefanik was named as Trump’s first pick to be U.S. ambassador to the United Nations. But Smullen, the only nominee running in the Conservative Party primary, will be on the November ballot regardless of what happens Tuesday.