Will the Republicans win the Michigan Senate race in 2026?
Crossbook compares what two exchanges, Polymarket and Kalshi, charge for the same event, and publishes a permanent scored record of its own forecasts under published rules.
Tracked on one venue, with Crossbook's own call on the record.
Bid/ask midpoint · retrieved 2026-10-29T23:10:27.079Z. Venue quote-update time is unavailable. Readings can be asynchronous.
23.5%bid 23.0% / ask 24.0%24h volume $355K · liquidity $421Kas of 29 Oct, 23:10 UTCView on PolymarketPrice, last 60 days
Crossbook forecast
- 19.8%against a market price of 25.5% at the timeOpen
Logged 29 Oct 2026, 20:01 UTC
- The dominant signal is the Oct. 26–27 likely-voter poll showing El-Sayed 51% and Rogers 44%; a seven-point deficit five days before the Nov. 3 election implies a low-teens comeback probability rather than a near-coin flip.
- The matchup is settled and the resolution target is simple: Republican nominee Mike Rogers must win the open Michigan Senate seat on Nov. 3.
- The open-seat context keeps the upset chance above zero: there is no Democratic incumbent because Gary Peters is retiring, and Michigan remains competitive enough that a Republican can win with a late shift or polling miss.
- Endorsements are mostly narrative rather than fresh measurable signal: Harris and Peters back El-Sayed while Trump backs Rogers, pointing in opposite partisan directions and likely already reflected in the polling.
What would change it: A credible final polling average or election-eve survey showing Rogers tied, ahead, or within about two points would sharply raise the Republican probability.
t-0285
Polymarket prices this at 23.5%. No verified equivalent is currently listed on the other venue, so there is no cross venue comparison on this page.
Volume over the last 24 hours is heavy, at about $355,281 on the busier venue. It closes in 5 days. Prices this close to resolution move on news rather than on reassessment.
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