Village in Grundy County and LaSalle County, Illinois
Seneca
District lines run through Seneca, so who represents you here depends on your street. Search your address to see yours.
Who lives in Seneca
Census survey estimates for 2020 to 2024, rounded.
People
- Population
- 2,500
- Median age
- 35.5 years
- Under 18
- 29%
- 65 and over
- 12%
- Veterans, of adults
- 11%
- Speak another language at home
- 3%
Race and ethnicity
- Hispanic or Latino, of any race
- 10%
- White, not Hispanic
- 87%
- Black, not Hispanic
- 1%
- Asian, not Hispanic
- 0%
Income and housing
- Median household income
- $86,800
- Below the poverty line
- 22%
- Bachelor's or higher, adults 25+
- 15%
- Owner-occupied homes
- 81%
- Median home value
- $228,000
2024 vote for president
Not counted for Seneca on its own: its precincts follow township lines, not the town’s. See the figures for Grundy County and LaSalle County.
Represent all of Seneca
Represent part of Seneca
Each represents the part of Seneca inside their district. Under each is how many people lived in that part at the 2020 Census, of 2,353 in all.
Lauren UnderwoodU.S. Representative, District 14, Democratic2,210 people in this part
Darin LaHoodU.S. Representative, District 16, Republican143 people in this part- SRSue RezinState Senator, District 38, Republican1,201 people in this part
- CBChris BalkemaState Senator, District 53, Republican1,152 people in this part
- JDJed DavisState Representative, District 75, Republican1,201 people in this part
- JBJason BuntingState Representative, District 106, Republican1,152 people in this part
Seneca's districts
U.S. House District 14
Part of Seneca: 2,210 people in 2020
Held by Lauren Underwood, Democratic
- Washington office: (202) 225-2976
About 763,800 people, median household income $95,500.
Largest towns: Joliet (part), Aurora (part), Plainfield and 77 more
U.S. House District 16
Part of Seneca: 143 people in 2020
Held by Darin LaHood, Republican
- Washington office: (202) 225-6201
About 748,900 people, median household income $84,400.
Largest towns: Bloomington (part), Pekin (part), Peoria (part) and 210 more
Illinois Senate District 38
Part of Seneca: 1,201 people in 2020
Held by Sue Rezin, Republican
- Springfield office: (217) 782-3840
- District office: (815) 220-8720
Illinois Senate District 53
Part of Seneca: 1,152 people in 2020
Held by Chris Balkema, Republican
- Springfield office: (217) 782-6597
- District office: (815) 844-9179
About 214,300 people, median household income $78,800.
Largest towns: Washington (part), Streator, Pontiac and 104 more
Illinois House District 75
Part of Seneca: 1,201 people in 2020
Held by Jed Davis, Republican
- Springfield office: (217) 782-5997
- District office: (331) 867-8200
Illinois House District 106
Part of Seneca: 1,152 people in 2020
Held by Jason Bunting, Republican
- Springfield office: (217) 558-1039
- District office: (779) 218-3070
Source: U.S. Census Bureau, American Community Survey 5-year estimates, 2020–2024; towns and counties from the 2020 Census, 119th Congressional District and 2024 state legislative district tabulation. Figures rounded by us. Retrieved 2026-10-19. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.
Source: U.S. Census Bureau, American Community Survey 5-year estimates, 2020–2024; towns and counties from the 2020 Census, 119th Congressional District and 2024 state legislative district tabulation. Figures rounded by us. Retrieved 2026-10-19. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.