Polling has been scant ahead of New York’s key contested congressional primaries on Tuesday, but bettors on Polymarket are focusing on predicting the winner of four contests — including three where socialist Mayor Zohran Mamdani has backed a candidate.

Five-term incumbent Rep. Adriano Espaillat was listed as having a 57% chance of winning re-election on the prediction market, compared to a 45% chance for Mamdani-backed Democratic socialist insurgent Darializa Avila Chevalier in the 13th House district covering northern Manhattan and parts of The Bronx. 

Meanwhile, Mamdani-backed Democratic Assemblywoman Claire Valdez has an 83% chance of winning, compared to 18% odds for Brooklyn Borough President Antonio Reynoso in the race to succeed retiring Rep. Nydia Velazquez in Brooklyn-Queens District 7.

Former city Comptroller and mayoral candidate Brad Lander has a 99% chance of winning the affluent 10th Big Apple congressional district, which covers parts of brownstone Brooklyn and lower Manhattan, according to the prediction market — compared to just 1% for two-term incumbent Rep. Dan Goldman.

Lander is also backed by Mamdani. 

In the 12th District, covering the Upper East and West Sides of Manhattan, bettors are banking on Assemblyman Micah Lasher, giving him a 59% chance of replacing retiring Rep. Jerry Nadler.

Assemblyman Alex Bores, meanwhile, is running with a 43% chance of winning, according to Polymarket. Jack Schlossberg, the grandson of former President John F. Kennedy, has only a 1% chance.

While Polymarket bettors might be focused on those four key congressional primaries, there are other House races worth noting, including:

• The bruising Republican primary to replace retiring upstate Rep. Elise Stefanik in CD 21. President Trump-backed Sticker Mule CEO Anthony Constantino is running against  Assemblyman Robert Smullen, who is the candidate of the New York Republican establishment and the state Conservative Party. Stefanik has not endorsed a successor.
• The Democratic primary to take on Republican Rep. Mike Lawler in the general election in Hudson Valley’s CD 17. Front-runners are Rockland County legislator Beth Davidson and Cait Conley, an Army vet and counterterrorism official under former President Joe Biden. Republicans perceive Conley as the more dangerous threat to Lawler in the swing district because of her military background, and Republicans have already spent money attacking her.

• In House District 3 covering parts of Nassau and Queens, Republican lawyer Greg Hach is primarying Assemblyman Michael Lipetri for the right to take on Democratic Rep. Tom Suozzi. Lipetri lost by only 3 points to Suozzi in 2024 and has the backing of President Trump, Vice President JD Vance, and the Nassau County GOP. Rudy Giuliani endorsed Hach, in a rare split with his pal Trump.