ToplineElection betting odds sharply swung away from Rep. Thomas Massie, R-Ky., not long after polls closed for his congressional district’s primary Tuesday, marking a massive reversal for the incumbent who lost the race after being favored for much of the campaign to win it over Trump-backed former Navy Seal Ed Gallrein.Massie is one of the GOP's most outspoken critics of President Donald Trump. (Photo by Heather Diehl/Getty Images)Key FactsGallrein had 99.5% odds, Kalshi showed shortly after 7:45 p.m. EDT, while Polymarket showed 99.8% odds for the Trump-endorsed challenger, just minutes before the Associated Press called the race for Gallrein. Massie’s odds had been above 40% on Kalshi in the minutes after polls closed, but before the first votes were reported, and he had been shown on the platform as recently as this weekend as the favorite to win the race. Massie had odds as high as 78% of winning the primary race less than two weeks ago, Kalshi showed.Big Number$21.9 million. That is the amount of money Kalshi users put into the proposition.Key BackgroundMassie has held his seat in Congress for well over a decade and has broken from President Donald Trump on several matters, opposing his war against Iran and voting against the “One Big Beautiful Bill.” He also co-authored the legislation forcing the government to release the Epstein files and has continued pressing the Trump administration over its handling and release of the documents. Massie has opposed aid to Israel and Ukraine. His opposition to Trump resulted in the president’s endorsement of Gallrein. Trump launched a rapid attack against Massie ahead of Tuesday’s primary, blasting the congressman almost a dozen times in two days and calling him an “obstructionist and a fool.” Nearly $33 million was spent in the fiery race, becoming the most expensive House primary race recorded by media tracking firm AdImpact since it started tracking primary financial figures in 2018. Further ReadingTrump Makes First X Post In Months, Trashes Thomas Massie (Forbes)Trump Has Posted About Massie At Least 11 Times In 2 Days Ahead Of Tuesday’s Primary (Forbes)