A federal appeals court has legalized election betting in the run-up to the November presidential vote, handing a defeat--at least temporarily--to regulators’ last-ditch battle against the emergence of U.S. political betting markets. In an order released Wednesday, the U.S. Court of Appeals for the District of Columbia Circuit lifted a temporary stay that had blocked Kalshi, a prediction-market startup, from launching contracts tied to which political party wins control of the two houses of Congress. Kalshi resumed trading in its congressional-control contracts just after the ruling.