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Illinois's 12th Congressional District
The current officeholder, the 2024 result, and a precinct-level model you can run yourself — built from how Illinois actually voted.
Model Illinois's 12th Congressional District →
Current officeholder
Mike Bost Republican
2024 result
Republican R+48.3
2024 votes cast
368,056
Office
U.S. House
Who lives in this district
This district is home to about 748,190 people, median age 41.4, median household income $66,758.
Population
748,190
Median age
41.4
Median household income
$66,758
Bachelor's degree or higher
24.1%
Race & ethnicity: White 87.6% · Black 4.9% · Hispanic 3% · Asian 1%
Source: U.S. Census Bureau, 2019–2023 American Community Survey (5-year).
Precinct results — 2024 general
859 precincts reported in Illinois's 12th Congressional District's 2024 general election. The twenty largest:
| Precinct | Winner | Margin | Votes |
|---|---|---|---|
| 17163-MASCOUTAH 3 | Republican | R+35.1 | 1,577 |
| 17163-MASCOUTAH 2 | Republican | R+30.6 | 1,297 |
| 17163-STOOKEY 1 | Republican | R+42.7 | 1,284 |
| 17163-O FALLON 16 | Republican | R+26.1 | 1,250 |
| 17163-CASEYVILLE 6 | Republican | R+17.8 | 1,226 |
| 17163-SHILOH VALLEY 5 | Republican | R+0.3 | 1,211 |
| 17163-MILLSTADT 2 | Republican | R+44.0 | 1,206 |
| 17163-LEBANON 1 | Republican | R+13.6 | 1,203 |
| 17133-PRECINCT 1 | Republican | R+35.6 | 1,186 |
| 17163-BELLEVILLE 5 | Republican | R+29.0 | 1,163 |
| 17163-O FALLON 8 | Republican | R+9.7 | 1,134 |
| 17133-PRECINCT 21 | Republican | R+54.1 | 1,129 |
| 17133-PRECINCT 9 | Republican | R+43.6 | 1,127 |
| 17163-O FALLON 12 | Republican | R+12.7 | 1,120 |
| 17055-BENTON 5 | Republican | R+52.5 | 1,098 |
| 17163-MARISSA 1 | Republican | R+62.5 | 1,092 |
| 17163-PRAIRIE DU LONG 2 | Republican | R+55.8 | 1,086 |
| 17163-O FALLON 15 | Republican | R+17.0 | 1,084 |
| 17163-SHILOH VALLEY 1 | Republican | R+16.8 | 1,079 |
| 17163-CASEYVILLE 18 | Democratic | D+0.8 | 1,063 |
All 859 precincts are modelable — open the race in the simulator and drill to precinct grain.
Find your district
Enter a ZIP code or a district (e.g. NC-4) to find your U.S. House district and who represents it.
Model Illinois's 12th Congressional District in five steps
- Set the candidates. Name the contenders for the Illinois's 12th Congressional District (or keep the generic Democrat / Republican defaults). The map starts from the canonical mixed-grain 2024 presidential baseline.
- Apply a swing. Move vote share statewide, or by demographic cohort, with a slider. The map and the running tally recompute instantly.
- Model turnout. Mobilize or depress turnout for any group — turnout and persuasion are modeled separately, the way a real campaign thinks about them.
- Explore local geography. Zoom from the state through counties to the finest supported reporting grain and adjust the places available in the model.
- Roll up & share. Roll the result up to chamber control, then share the exact versioned scenario.
Open Illinois's 12th Congressional District in the simulator →