Overview
- District ID
- il-hd-104
- State
- Illinois
- Chamber
- Lower chamber
- District Code
- 104
- Land Area
- 563.2 sq mi
- Water Area
- 2.81 sq mi
Boundary
Boundary as GeoJSON
Source: U.S. Census Bureau TIGER/Line state legislative district boundaries.
Counties
Showing all 2 counties
Places
Showing all 16 places
Overlapping Congressional Districts
| Congressional district | Population in both | Share of this district's population | Share of the congressional district's population | Share of this district's land |
|---|
| IL District 2 | 63,412 | 58.4% | 8.4% | 53.2% |
| IL District 13 | 40,074 | 36.9% | 5.3% | 13.2% |
| IL District 15 | 5,126 | 4.7% | 0.7% | 33.5% |
Source: U.S. Census Bureau 2020 blocks and 2025 block equivalency files (119th Congress, 2024 state legislative plans).
Voters
- Registered Voters
- 72,198
- Active Voters
- 69,456 (96.2%)
Party Registration
This state's voter file does not record party registration.
Turnout by Cycle
| Cycle | General | Democratic Primary | Republican Primary |
|---|
| 2025–2026 | 14,129 (19.6%) | 756 (1.0%) | 0 (0.0%) |
| 2023–2024 | 47,835 (66.3%) | 4,888 (6.8%) | 5,313 (7.4%) |
| 2021–2022 | 35,852 (49.7%) | 6,170 (8.5%) | 8,390 (11.6%) |
| 2019–2020 | 44,415 (61.5%) | 9,943 (13.8%) | 6,423 (8.9%) |
| 2017–2018 | 34,479 (47.8%) | 7,459 (10.3%) | 6,861 (9.5%) |
| 2015–2016 | 36,849 (51.0%) | 9,791 (13.6%) | 12,352 (17.1%) |
| 2013–2014 | 24,809 (34.4%) | 3,121 (4.3%) | 6,411 (8.9%) |
| 2011–2012 | 29,785 (41.3%) | 2,530 (3.5%) | 6,632 (9.2%) |
Turnout counts today's registered voters with a counted ballot in the cycle's elections (the odd and even year), as a share of today's registered voters. Voters who have since left the rolls are not counted.
Browse the voter list for this district (premium access; sign-in required)
Source: Civitech voter file snapshot as of 12/15/2025. These are registered voters, separate from the Census population figures. Counts under 10 are suppressed and shown as "<10".
Demographics
- Total Population
- 109,398 (± 1,631)
- Median Age
- 40.7
- Median Household Income
- $68,114 (± $3,427)
- High School Graduate or Higher (age 25+)
- 93.1%
- Bachelor's Degree or Higher (age 25+)
- 34.8%
Population by Age
| Group | People | Share |
|---|
| Under 18 | 25,161 | 23.0% |
| 18 to 64 | 61,946 | 56.6% |
| 65 and over | 22,291 | 20.4% |
Population by Race and Hispanic Origin
| Group | People | Share |
|---|
| Hispanic or Latino (any race) | 8,095 | 7.4% |
| White, not Hispanic | 72,533 | 66.3% |
| Black, not Hispanic | 16,419 | 15.0% |
| Asian, not Hispanic | 7,608 | 7.0% |
| American Indian / Alaska Native, not Hispanic | 53 | 0.0% |
| Native Hawaiian / Pacific Islander, not Hispanic | 5 | 0.0% |
| Some other race, not Hispanic | 439 | 0.4% |
| Two or more races, not Hispanic | 4,246 | 3.9% |
Source: U.S. Census Bureau, American Community Survey 2020-2024 ACS 5-year estimates (tables B01001, B01002, B01003, B03002, B15003, B19013) for this state legislative district. Estimates are survey-based; ± figures are 90% margins of error.
Citizen Voting Age Population
- Total Citizen Population
- 104,180
- Citizen Voting Age Population (CVAP)
- 79,502
Citizen Population by Race/Ethnicity
| Group | Citizens | Share |
|---|
| Non-Hispanic | 97,476 | 93.6% |
| Hispanic | 6,707 | 6.4% |
| White | 72,604 | 69.7% |
| Black | 16,237 | 15.6% |
| Asian | 4,778 | 4.6% |
| American Indian / Alaska Native | 51 | 0.0% |
| Native Hawaiian / Pacific Islander | 3 | 0.0% |
| Two or More Races | 337 | 0.3% |
Citizen Voting Age Population by Race/Ethnicity
| Group | CVAP | Share |
|---|
| Non-Hispanic | 75,724 | 95.2% |
| Hispanic | 3,775 | 4.7% |
| White | 60,194 | 75.7% |
| Black | 11,587 | 14.6% |
| Asian | 3,417 | 4.3% |
| American Indian / Alaska Native | 634 | 0.8% |
| Native Hawaiian / Pacific Islander | 0 | 0.0% |
| Two or More Races | 151 | 0.2% |
Source: Redistricting Data Hub / U.S. Census Bureau CVAP Special Tabulation (2020-2024 ACS 5-year).
