Who is forecasted today to win the Kansas Senate race?
Updated Monday, October 26, 2026 · 8 days to Election Day · VotePredictor
Roger Marshall is favored. The VotePredictor forecast gives Marshall a 79% chance of beating Adam Hamilton, with a predicted margin of Marshall +2.8. That is a Lean R race: Marshall wins about three times in four, and Hamilton in the other 21%.
What the forecast is built on
The forecast starts from the 9 public polls in the forecast window, whose plain average is Hamilton +0.7. Each poll is corrected for its voter screen and its pollster's measured house effect first (the “Adjusted” column below).
- The polls, weighted and corrected, read Marshall +1.4.
- The fundamentals (the state's presidential lean, incumbency, the last result and the national environment) read Marshall +14.5.
- The published forecast blends the two, mostly on the polls, at Marshall +2.8.
Misses of a few points are common, so a 2.8-point lead is a 79% chance and not a lock.
How the forecast has moved
| Date | Marshall's chance | Predicted margin |
|---|---|---|
| Apr 2 | 82% | Marshall +14.4 |
| May 7 | 76% | Marshall +10.7 |
| Jun 4 | 76% | Marshall +10.7 |
| Jul 2 | 76% | Marshall +10.7 |
| Aug 6 | 76% | Marshall +10.7 |
| Sep 1 | 76% | Marshall +7.1 |
| Oct 1 | 75% | Marshall +2.7 |
| Oct 19 | 72% | Marshall +1.9 |
| Oct 26 (today) | 79% | Marshall +2.8 |
The polls
9 polls are in today's forecast; 2 older ones have aged out and are shown dimmed. Margins are Democrat minus Republican.
The polls behind it
11 polls · 9 in today's forecast · newest firstDimmed polls are more than 61 days old. They stay on the record, but today's forecast no longer counts them. Each pollster name links to the poll's source.The VotePredictor margin is the poll after correcting for its pollster's record in past elections and for registered-voter or all-adult samples.
What everyone else says
Prediction markets
| Market | Marshall's chance |
|---|---|
| Polymarket | 63% |
| Kalshi | 61% |
| VotePredictor | 79% |
Rating shops
| Forecaster | Rating | As of |
|---|---|---|
| Cook Political Report | Toss-up | Oct 20, 2026 |
| The Economist | Toss-up | Oct 26, 2026 |
| FiftyPlusOne | Toss-up | Oct 25, 2026 |
| NBC News | Toss-up | Oct 25, 2026 |
| RealClearPolitics | Toss-up | Oct 25, 2026 |
| Sabato's Crystal Ball | Toss-up | Oct 14, 2026 |
| Silver Bulletin | Toss-up | Oct 25, 2026 |
| Inside Elections | Tilt R | Oct 15, 2026 |
| Decision Desk HQ | Lean R | Oct 26, 2026 |
| Fox News | Lean R | Oct 20, 2026 |
| Split Ticket | Lean R | Oct 22, 2026 |
4 of 11 rating shops favor Marshall, 7 call it a toss-up and none favor Hamilton. The markets average 62% for Marshall; VotePredictor is 18 points more confident in Marshall.
Can you trust this forecast?
Every VotePredictor forecast is scored after the election against the same outcomes as everyone else's. Across 615 past races (Senate, governor, House and president), our final forecasts rank #2 of every forecaster that covered them all (Brier score 0.075, lower is better); FiveThirtyEight is first at 0.074. The full record is on the forecaster rankings and methodology pages.
This article is regenerated every day from the VotePredictor forecast, the poll database, the prediction markets and the rating shops' latest published ratings. Live numbers are on the race page.