2026 state legislative forecast
Illinois Senate forecast
Democrats win control of the Illinois Senate in nearly every one of 2,000 simulations, against a Democratic majority today. 39 of the 59 seats are on the 2026 ballot and 20 carry over until 2028; 1 race is within a 35 to 65 split.
Chance of control
>99%D<1%R
Democratic seats, 80% range
44 to 47Median 46 · 30 for a majority
Favored to flip
7to D0to R
After 2024: 39 D, 19 R
Environment
D +12.7Shift from the 2024 presidential vote
Illinois Senate map
Safe DLean DToss upLean RSafe RNot up in 2026
District shapes are estimated from where each district's voters live in the precinct returns, not drawn from the official boundary files.
Pick a district
Hover the map for the odds in any district. Click one to pin it here and find it in the table below.
Every seat
Average 46 D to 13 RSafe DLean DToss upLean RSafe RNot up
Democratic seats across 2,000 simulations
Every Senate district
| District | Last winner | 2026 nominees | 2024 lean | Forecast | Dem win | Rating |
|---|---|---|---|---|---|---|
| 32 | Craig Wilcox 2022 | Karen Battaglia vs Craig Wilcox | R +6.3 | D +1.6 | 59% | Toss up |
| 35 | Dave Syverson 2022 | Sarah B. Mertens vs Dave Syverson | R +9.8 | D +2.9 | 68% | Lean D |
| 38 | Sue Rezin 2022 | Ernie R. Marcelain vs Sue Rezin | R +6.7 | D +6.0 | 81% | Likely D |
| 24 | Seth Lewis 2022 | Benjamin "Ben" McAdams vs Seth Lewis | D +3.4 | D +11.5 | 97% | Likely D |
| 56 | Erica Conway Harriss 2022 | Marsia Geldert-Murphey vs Erica Harriss | R +1.9 | D +11.8 | 95% | Likely D |
How this is built
Each district starts from its 2024 presidential vote, read off the precincts that voted in it, and moves with the state's 2026 House forecast and the national generic ballot. Half of what the last legislative winner ran ahead of the district carries over, 2026 primary turnout moves districts where it is posted, and district and statewide legislative polls count by recency and sample. A seat with no candidate from one party is called for the other. 2,000 simulations share a national, a state and a district shock. The map's district shapes are estimated from where each district's voters are in the precinct returns. All chambers.