Major decisions about who will be New York City’s next top mayoral candidate are set to be made Tuesday, and millions of Americans are betting live on their election odds.

Event contract platform Kalshi recently launched market predictions for multiple NYC election-related prompts, including who will reign in the top spot for Democratic mayoral nominee and the overall race winner.

The 2025 race for New York City mayor is tightening, with former Gov. Andrew Cuomo’s lead shrinking less than a week ahead of the crucial primary, a poll indicated. Zohran Mamdani, a 33-year-old Democratic socialist state assemblyman from Queens, stands in second place in the poll.

As of Tuesday morning, Kalshi showed Mamdani with a 56% chance of winning the Democratic Party nomination this year, and Cuomo with a 44% chance. Bettors have poured more than $8 million into the total series volume, according to Kalshi’s website.

ELECTION ‘WHALE’ BETTOR MADE MUCH MORE ON TRUMP WIN THAN ORIGINALLY THOUGHT, ANALYSIS SHOWS

Buying a “yes” share for Mamdani costs roughly $0.57 while a “no” share costs $0.46; Cuomo’s “yes” share can be bought for roughly $0.46 and a “no” share for $0.56.

One Kalshi user posted in the comment section that his $984.75 investment on Mamdani being confirmed as the Democrats’ nominee would make a return of $1,968.96.

Another prediction market asks bettors who will reign as the NYC mayoral race winner between a Democrat, Republican or current Mayor Eric Adams. Eighty-two percent of bettors predicted a Democrat will win, with 12% for Eric Adams and 7% for a Republican.

Because of the large consensus for a Democratic candidate winning the blue city election, buying a “yes” share costs $0.83 and a “no” share costs $0.19.

In general, prediction markets like Kalshi and other platforms, including Polymarket and PredictIt, allow users to trade on the outcome of future events with yes-no questions. Individual trades are between $0 and $1, and contracts pay $1 if the event occurs.

While primary voting will take place until 9 p.m. ET Tuesday, more than 384,000 Democrats cast ballots in early voting, which ended on Sunday.

GET FOX BUSINESS ON THE GO BY CLICKING HERE

The winner of the Democratic Party primary is traditionally seen as the overwhelming frontrunner in the November general election in the Democrat-dominated city.

However, this year, the general election campaign may be a bit more unpredictable with incumbent Adams running for reelection as an Independent and his approval ratings sinking to historic lows.

READ MORE FROM FOX BUSINESS

Fox News’ Paul Steinhauser and Pilar Arias contributed to this report.