Who is forecasted today to win the Idaho Senate race?
Updated Monday, October 26, 2026 · 8 days to Election Day · VotePredictor
Jim Risch is favored. The VotePredictor forecast gives Risch a 99% chance of beating David Roth, with a predicted margin of Risch +33.8. That is a Safe R race: Risch wins in nearly every simulation, and Roth in the other 1%.
What the forecast is built on
The forecast starts from the 3 public polls in the forecast window, whose plain average is Risch +29.0. 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 Risch +35.1.
- The fundamentals (the state's presidential lean, incumbency, the last result and the national environment) read Risch +30.7.
- The published forecast blends the two, mostly on the polls, at Risch +33.8.
How the forecast has moved
| Date | Risch's chance | Predicted margin |
|---|---|---|
| Jun 4 | 96% | Risch +27.6 |
| Jul 2 | >99% | Risch +36.1 |
| Aug 6 | >99% | Risch +36.1 |
| Sep 1 | >99% | Risch +31.9 |
| Oct 1 | >99% | Risch +35.2 |
| Oct 19 | >99% | Risch +33.7 |
| Oct 26 (today) | 99% | Risch +33.8 |
The polls
3 polls are in today's forecast. Margins are Democrat minus Republican.
The polls behind it
3 polls · newest firstEach 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 | Risch's chance |
|---|---|
| Polymarket | >99% |
| Kalshi | >99% |
| VotePredictor | 99% |
Rating shops
| Forecaster | Rating | As of |
|---|---|---|
| Cook Political Report | Solid R | Oct 20, 2026 |
| Decision Desk HQ | Solid R | Oct 26, 2026 |
| The Economist | Solid R | Oct 26, 2026 |
| FiftyPlusOne | Solid R | Oct 25, 2026 |
| Fox News | Solid R | Oct 20, 2026 |
| Inside Elections | Solid R | Oct 15, 2026 |
| NBC News | Solid R | Oct 25, 2026 |
| RealClearPolitics | Solid R | Oct 25, 2026 |
| Sabato's Crystal Ball | Solid R | Oct 14, 2026 |
| Silver Bulletin | Solid R | Oct 25, 2026 |
| Split Ticket | Solid R | Oct 22, 2026 |
All 11 rating shops favor Risch. The markets average >99% for Risch; VotePredictor is in line with them.
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.