Which party will win the U.S. Senate?
Sikt’s forecast: Democrats 56%. Sikt reads the news and data that exist today, checks every source, and independent AI forecasters agree on one probability. Each Bench round adds a green point next to the market’s daily price on Kalshi and Polymarket, and every forecast will be graded when the result is known.
Chance: Democratic Party
Sikt 56%Kalshi 64%Polymarket 64%
Every round
Chance the Democratic Party wins control of the U.S. Senate. Market prices are from the same day; the gap is Sikt minus the average of the two markets, in points. Version is the release of Sikt that made the forecast.
| Round | Snapshot (UTC) | Sikt | Kalshi | Polymarket | Gap | Version |
|---|---|---|---|---|---|---|
| R1 | Sep 30, 12:56 | 53% | 62% | 62% | -9 | 1.0 |
| R2 | Oct 3, 15:00 | 56% | 63% | 64% | -8 | 1.2 |
All outcomes, latest round
| Outcome | Sikt | Kalshi | Polymarket |
|---|---|---|---|
| Democratic Party | 56% | 64% | 64% |
| Republican Party | 43% | 36% | 36% |
How it resolves
- Kalshi, “Which party will win the U.S. Senate?”: If the Democratic Party has won control of the U.S. Senate in 2026, then the market resolves to Yes. Full rules
- Polymarket, “Which party will win the Senate in 2026?”: This market will resolve according to the party that wins control of the United States Senate in the 2026 United States midterm election. A party wins control of the United States Senate if it wins a majority of the chamber’s voting seats. Full rules
Get Sikt’s next forecasts
Race-by-race previews from the Sikt Midterm Bench follow on October 13.
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Sikt forecasts are research previews from the Sikt Midterm Bench. Market data from the public Kalshi and Polymarket APIs, shown for information only; prices can be several hours old. Sikt Intelligence is not affiliated with Kalshi or Polymarket. Not financial or investment advice.