The startup’s runaway success this year has been a sore point for Kalshi, a regulated, dollar-denominated prediction market that’s been fighting a protracted court battle with its supervisor, the U.S. Commodity Futures Trading Commission, so it can list contracts on which party will control each house of Congress. The agency has been considering a proposed rule that would ban election event contracts at all the exchanges on its watch, which would push regulation of such activity to the states.