2026 Illinois · U.S. House
IL-12 House race odds
As of Oct 4, 2026, prediction markets give Republican Mike Bost a 97% chance of winning the 2026 race for IL-12 over Democrat Julie Fortier (Kalshi 97%, Polymarket 97%).
$32K traded · updated · prices refresh every 10 minutes
- Parlay estimate how?
- R 100% vs. market 97%
- Market rating
- Safe R
- Kalshi (D / R)
- 3.3% / 96.7%
- Polymarket (D / R)
- 3.1% / 96.9%
- Total traded
- $32K
- Gap between exchanges
- 0.2 pts
- Election Day
- Nov 3, 2026 (31 days)
Polls
No general-election polls of this race are listed yet. See RealClearPolitics for its poll listings.
Share prices
Each contract pays $1 if that outcome happens. The price is what traders are paying now, so 60¢ means roughly a 60% chance. Bid is the best offer to buy, ask the best offer to sell.
| Contract | Price | Bid | Ask | Last | 24h |
|---|---|---|---|---|---|
| Mike Bost | 95¢ | 93¢ | 97¢ | 95¢ | 0¢ |
| Julie Fortier | 3¢ | 1¢ | 6¢ | 8¢ | 0¢ |
| Contract | Price | Bid | Ask | Last | 24h |
|---|---|---|---|---|---|
| Mike Bost | 96¢ | 94¢ | 97¢ | 97¢ | 0¢ |
| Julie Fortier | 3¢ | 2¢ | 4¢ | 4¢ | 0¢ |
Market activity
How much is trading, where the money is going, and the live order book.
Trade records begin Sep 30. Peak day: $664.
Biggest trades on this race
- $475Yes Mike Bost at 95¢Kalshi · 3d ago
- $95Yes Mike Bost at 95¢Kalshi · 3d ago
- $95Yes Mike Bost at 95¢Kalshi · 3d ago
Money flow · last 24 hours
Order book · Polymarket · Mike Bost
Loading the live order book…
Money waiting to buy (green) and sell (red) at each price. Refreshes every 30 seconds.
Trade tape
Connecting…| When | Exchange | Trade | Price | Amount |
|---|---|---|---|---|
| Loading trades… | ||||
Polymarket trades appear live. Kalshi trades are collected every 10 minutes for the most active contracts. Blue backs the Democrat, red the Republican.
Price history
Democratic odds fell 1.0 points over the past 3 months, from 4% to 3%.
Every candidate, by exchange
Each exchange's prices rescaled to add up to 100%. Kalshi prices are the bid–ask midpoint; Polymarket prices are its displayed price.
Kalshi open market ↗
| Outcome | Chance | Volume |
|---|---|---|
| Mike Bost (R) | 96.7% | $5K |
| Julie Fortier (D) | 3.3% | $3K |
Polymarket open market ↗
| Outcome | Chance | Volume |
|---|---|---|
| Mike Bost (R) | 96.9% | $14K |
| Julie Fortier (D) | 3.1% | $11K |
Questions about this race
Who is favored to win the 2026 IL-12 House race?
As of Oct 4, 2026, prediction markets give Republican Mike Bost a 97% chance of winning the 2026 race for IL-12 over Democrat Julie Fortier (Kalshi 97%, Polymarket 97%).
What do Kalshi and Polymarket say?
Kalshi: Democrats 3%, Republicans 97%. Polymarket: Democrats 3%, Republicans 97%. The two exchanges differ by 0.2 points.
How have the odds moved this week?
Democratic odds have fallen 1.1 points since Sep 27, 2026.
What is the Parlay estimate for the 2026 IL-12 House race?
The Parlay estimate gives Republicans 100%, against 97% in the markets. Our model, trained on decided races, finds that clear favorites win more often than their prices imply.
How much money has been traded on the 2026 IL-12 House race?
$32K has traded on Kalshi and Polymarket combined, $664 of it in the past 7 days.
When is the 2026 election?
Election Day is Nov 3, 2026, 31 days from now.
Other Illinois races in 2026
- Illinois GovernorD 97% · $131K
- IL-01 HouseD 96% · $61K
- IL-10 HouseD 98% · $35K
- IL-11 HouseD 99% · $47K
- IL-13 HouseD 96% · $23K
- IL-14 HouseD 98% · $21K
- IL-15 HouseR 96% · $47K
- IL-16 HouseR 95% · $90K
- IL-17 HouseD 99% · $36K
- IL-02 HouseD 97% · $35K
- IL-03 HouseD 97% · $53K
- IL-04 HouseD 95% · $79K
- IL-05 HouseD 98% · $30K
- IL-06 HouseD 97% · $44K
- IL-07 HouseD 98% · $27K
- IL-08 HouseD 94% · $30K
- IL-09 HouseD 96% · $35K
- Illinois SenateD 98% · $52K
Closest House races in 2026
Data
Price history (JSON)All 2026 races (JSON)All 2026 races (CSV)2026 dashboardMethodology
Cite as: Parlay the People, “2026 IL-12 House race,” https://parlaythepeople.com/2026/house/il-12/, accessed Oct 4, 2026. Prediction-market prices are crowd forecasts, not certainties, and nothing here is betting or investment advice.
