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Two online platforms are taking bets on Maine’s 2026 elections, allowing users to put early money on which party will win the U.S. Senate race and who will take crowded primaries.
The nascent and controversial market is dominated by Kalshi and Polymarket, the latter of which is putting American users on a waitlist after securing regulatory approval to operate here this week after a pause of roughly three years. These platforms did better than polls in reflecting President Donald Trump’s victory in the 2024 election.
Bets on Maine elections were available that year, with Kalshi users putting $1.7 million on the winner of the state in the presidential election. But their use will likely explode in 2026, with wagers already exceeding $1.1 million on the winner of the buzzy Democratic primary for the right to face U.S. Sen, Susan Collins in next year’s election.
Kalshi offers “futures contracts” that give users binary choices on current events and sports. For example, it gives upstart oyster farmer Graham Platner of Sullivan a 63% chance of winning the Senate primary over Gov. Janet Mills, who is at 36%. That percentage corresponds to a 63-cent price for a share in Platner that would pay $1 if he wins the June nominating race.
These platforms do not set odds like regulated sportsbooks do. They bill themselves as peer-to-peer platforms that match bets with conflicting ones. It can lead to strange figures in their markets. For example, Kalshi is still allowing users to bet on state Rep. Laurel Libby, R-Auburn, to be her party’s gubernatorial nominee even though she has ruled out a run.
Both Kalshi and Polymarket operate under federal securities laws. Their businesses are effectively extensions of a gambling market that has exploded in the U.S. since the landmark U.S. Supreme Court decision in 2018 and allowed states to regulate sports betting.
Maine is one of 38 states to do that so far through a law that reserved the lucrative online portion of the market for tribes. The Passamaquoddy have dominated it since bets opened in late 2023 through an exclusive deal with DraftKings, while the three other federally recognized tribes are aligned with Caesars Sportsbook.
States including Maine are wary of incursions into that market by Kalshi and Polymarket, which offer bets on sports without falling under state regulations. They are not alone. Earlier this month, the state’s gambling regulator issued a warning to platforms operating under sweepstakes laws that offer sports betting and casino-style games.
Maine does not allow the regulated sportsbooks to take bets on in-state college sporting events, but Polymarket was offering a market on the University of Maine’s Friday basketball game against American University. That was alongside another market on the 2026 Senate race, with Democrats as 70% favorites to knock off Collins and her Republicans.
In 2023, a group of Democratic senators urged a federal regulator to ban Kalshi from taking contracts on elections, citing risks of insider trading. Trump’s son, Donald Trump Jr., joined Kalshi as an adviser in January. The platforms have policies against insider trading and have responded to concerns from sports leagues by saying they want robust regulations.
“We, like them, want a safe, regulated platform that provides integrity reassurances,” a Kalshi official told ESPN earlier this year.
