A LED sphere screen shows information inside the new location of the prediction market online platform Polymarket called "The Situation Room", during its opening day in Washington, DC, on March 20, 2026. Prediction market platforms have rapidly broken into the mainstream in the United States, positioning themselves as an alternative to both traditional polling and licensed sports betting. Platforms like Polymarket and its biggest rival Kalshi, remain illegal or unregulated in most countries outside the US, where regulators have generally classified them as unlicensed gambling. (Photo by Théo MARIE-COURTOIS / AFP via Getty Images)