All 11 Democrats on the Senate Banking, Housing, and Urban Affairs Committee asked Chair Tim Scott to hold a public hearing on prediction markets, led by Ranking Member Elizabeth Warren and Catherine Cortez Masto. The request followed a private meeting between committee Republicans and Kalshi CEO Tarek Mansour. The senators want public scrutiny of consumer protection, manipulation, insider trading, market integrity and whether contracts tied to corporate performance could qualify as security-based swaps under Securities and Exchange Commission oversight. The CFTC regulates event contracts traded on registered derivatives exchanges, while Senate Banking oversees the SEC and securities markets, creating overlapping jurisdiction as prediction markets expand. Pew Research Center estimated combined monthly volume on Kalshi and Polymarket at about $53 billion in July 2026, up from $26 billion in May, while Bernstein projected annual industry volume could rise from roughly $410 billion in 2026 to about $10 trillion by 2035. The debate also encompasses sports-contract disputes, proposed stock and ETF perpetual futures, margin access for professional traders, and the possibility that U.S. rules will influence where platforms, capital and market data concentrate.