Kalshi and Polymarket both show Jackson crushing Collins in Maine Senate race
Both Kalshi and Polymarket show Democrat Troy Jackson heavily favored over Republican incumbent Susan Collins in Maine's U.S. Senate race. The Kalshi market depicts Jackson swamping Collins, according to a September 30 report. Political commentator Cillizza discussed Kalshi's Maine contract and Democratic sweep odds in a September 29 podcast, though offered no specific prices or trading data. The dual-platform consensus on Jackson follows sharp Kalshi repricing earlier in the week.
The dual-platform consensus strips away the arbitrage edge that institutional capital chased between Kalshi and Polymarket earlier this cycle. When both venues price the same candidate above 60%, cross-venue spread collapses and traders must find alpha elsewhere, usually in thinner state markets or by front-running poll releases.
Kalshi, matching Polymarket's sentiment on a high-profile race helps retain accounts that migrated for political liquidity, but it also surrenders the platform-specific signal that attracted them. SocGen's model now ingests these convergent prices, so any sudden divergence would force the bank to pick a venue and amplify the winner's credibility. The $9.7 million Maine book means small information advantages still pay, but only for the fastest participant base.
Jackson's heavy favoring on both venues builds on Kalshi's Maine Senate market repricing just days earlier, when traders moved Collins nine points on a single poll but still left Jackson above 60%, confirming Maine as this cycle's most actively repriced Senate race across regulated prediction markets.