Kalshi co-founder and CEO Tarek Mansour told CNBC he supports banning insider trading by members of Congress and executive branch officials, saying the company has monitored such activity since its 2018 launch. His comments come as some Democratic lawmakers pursue legislation that would go beyond insider-trading rules and prohibit election-related prediction-market trading altogether. Sen. Jeff Merkley and Rep. Jamie Raskin have introduced a bill that would also prohibit event contracts tied to sports, military action and major government activities. Kalshi, regulated by the CFTC, allows users to trade event contracts that pay $1 when a specified outcome occurs. The platform handled about $1.3 billion in midterm wagers by Monday, while Kalshi and Polymarket together had nearly $1.9 billion, according to a Washington Post analysis. The Senate barred its members and staff from trading election contracts in April. Mansour cited former Rep. George Santos, whom the CFTC ordered to pay about $35,000 over bets against himself, and said Kalshi opened an October investigation into bets on President Donald Trump's press secretary before the selection became public. Congress is weighing competing proposals, including the Merkley-Raskin bill and bipartisan legislation from Rep. Blake Moore focused on election outcomes. The eventual policy could determine whether U.S.-regulated platforms continue listing election contracts, a significant issue for Kalshi after it closed a $1 billion funding round at a $40 billion valuation in late October. CNBC disclosed a commercial relationship with Kalshi involving customer acquisition and a minority investment.