As of October 15, 2026, prediction markets have Democrats as favourites to win the Senate (about 63%) and strong favourites for the House (about 90%) in the November 3 midterms. Those prices come from Kalshi and Polymarket, where the control markets are the most liquid political contracts in the world right now. Below: the snapshot, the key races that make up the Senate number, and how the contracts actually settle, which is not on election night.
Control markets, October 15 snapshot
| Chamber | Kalshi (D) | Polymarket (D) | Average | Weekly change |
|---|---|---|---|---|
| Senate | 62.8¢ | 64¢ | 63% | +1 |
| House | 90.2¢ | 91¢ | 90% | 0 |
Prices move daily; this is a dated snapshot, not a live feed. Check the live contracts before trading.
Key Senate races (Kalshi, chance the Democrat wins)
| State | Race | D chance |
|---|---|---|
| Alaska | Peltola (D) vs Sullivan (R) | 74% |
| Michigan | El-Sayed (D) vs Rogers (R) | 69% |
| Texas | Talarico (D) vs Paxton (R) | 64% |
| Ohio (special) | Brown (D) vs Husted (R) | 60% |
| Maine | Jackson (D) vs Collins (R) | 57% |
| Iowa | Turek (D) vs Hinson (R) | 42% |
| Kansas | — | 37% |
| South Carolina | — | 15% |
| Nebraska | Osborn (I) vs Ricketts (R); "Democrat wins" priced under 1% | <1% (D) |
The Senate control price is roughly the probability that enough of these break Democratic. Texas, Maine and Ohio are where most of the uncertainty sits; Nebraska matters because an independent win wouldn't count as a Democratic seat in a "Democrat wins" contract but would affect control if Osborn caucuses with Democrats, which is exactly the kind of detail each contract's rules address.
How the contracts resolve
- Kalshi: there's no single Senate-control contract. The displayed probability is built from balance-of-power contracts that settle in February 2027 on actual control of the chamber, after certification and any runoffs. A network projection on election night doesn't settle anything.
- Polymarket: a single Senate-control contract with its own rules on independents, ties and vice-presidential tiebreaks. Read them.
- Individual races: each has a named settlement source and rules for recounts and runoffs. Georgia's runoff rule in particular can push settlement into December or January.
Where to trade
Kalshi (web and app, 18+), Polymarket US (web and app, 18+; politics markets available nearly everywhere), and the Kalshi-powered brokers (Robinhood, Coinbase, Plus500). Underdog and Gemini also list politics. Fees: Polymarket charges 4% × P × (1 − P) on politics for takers, Kalshi 7%; makers are free on both (Kalshi fees, Polymarket fees). Election contracts are the one category Kalshi fought its own regulator to list, in 2024; see the legal background. Washington state and Nevada block election markets on Kalshi.
Snapshot from DefiRate's midterms tracker (Oct 15, 2026, 11:23 AM ET) aggregating Kalshi and Polymarket. Not a recommendation.