Julie Fortier
DEMOCRATIC
Research Microbiologist
Illinois12th District2026 HOUSE FORECAST
Mike Bost*
REPUBLICAN
US House of Representatives (R-IL)
2015 – Present
2026 Illinois 12th District House Forecast:
Proprietary forecast for Illinois's 12th congressional district House election between Democrat Julie Fortier and Republican Mike Bost. This page will update with a daily set of 100,000 new simulations as race fundamentals change in order to produce race odds, projected margin, and forecasted vote share. This page also includes polling averages when available.
The 2026 Illinois 12th District House election features Democrat Julie Fortier and Republican Mike Bost. Incumbent Representative Mike Bost is seeking reelection to a seventh term. In 2024, Donald Trump won Illinois' 12th congressional district by 6.5%, and the election for the district's House seat is rated as solid Republican in 2026.
- Year
- 2026
- Race
- House
- District
- IL-12
- Democratic candidate
- Julie Fortier
- Republican candidate
- Mike Bost
- Incumbent / open seat
- Mike Bost
- Forecast rating
- Solid R
- Projected vote
- 30.0% D / 70.0% R
- Projected margin
- R +40.0
- Forecast odds
- 0.1% D / 99.9% R
- Forecast last updated
- 12:00 AM on July 2, 2026
- Polling average
- —
- Polling average margin
- —
- Polling last updated
- —
- Polls included
- 0
- Latest poll
- —