Colorado State House District 31

State Legislative District Profile (Lower Chamber)

Overview

District ID
co-hd-031
State
Colorado
Chamber
Lower chamber
District Code
031
Land Area
18.8 sq mi
Water Area
1.81 sq mi

Boundary

Boundary of Colorado State House District 31

Boundary as GeoJSON

Source: U.S. Census Bureau TIGER/Line state legislative district boundaries.

Counties

CountyOverlapShare of district landShare of county land
Adams County18.83 sq mi100.0%1.6%

Showing all 1 county

Places

PlaceOverlapShare of district landShare of place land
Thornton city15.18 sq mi80.7%41.6%
Sherrelwood CDP0.00 sq mi<0.1%<0.1%

Showing all 2 places

Overlapping Congressional Districts

Congressional districtPopulation in bothShare of this district's populationShare of the congressional district's populationShare of this district's land
CO District 886,865100.0%12.0%100.0%

Source: U.S. Census Bureau 2020 blocks and 2025 block equivalency files (119th Congress, 2024 state legislative plans).

Voters

Registered Voters
53,014
Active Voters
47,918 (90.4%)

Party Registration

PartyVotersShare
Democratic14,64427.6%
Republican8,59616.2%
Unaffiliated28,06052.9%
Other parties1,7143.2%
No party recorded00.0%

Turnout by Cycle

CycleGeneralDemocratic PrimaryRepublican Primary
2025–202614,227 (26.8%)0 (0.0%)0 (0.0%)
2023–202433,929 (64.0%)4,447 (8.4%)3,472 (6.5%)
2021–202223,114 (43.6%)3,370 (6.4%)2,444 (4.6%)
2019–202031,600 (59.6%)7,198 (13.6%)3,465 (6.5%)
2017–201820,804 (39.2%)3,646 (6.9%)1,875 (3.5%)
2015–201623,304 (44.0%)2,054 (3.9%)1,295 (2.4%)
2013–201414,108 (26.6%)1,583 (3.0%)1,403 (2.6%)
2011–201218,653 (35.2%)1,514 (2.9%)965 (1.8%)

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 01/20/2026. These are registered voters, separate from the Census population figures. Counts under 10 are suppressed and shown as "<10".

Demographics

Total Population
85,934 (± 2,470)
Median Age
33.1
Median Household Income
$90,165 (± $3,679)
High School Graduate or Higher (age 25+)
83.5%
Bachelor's Degree or Higher (age 25+)
25.4%

Population by Age

GroupPeopleShare
Under 1821,50025.0%
18 to 6456,30565.5%
65 and over8,1299.5%

Population by Race and Hispanic Origin

GroupPeopleShare
Hispanic or Latino (any race)41,82748.7%
White, not Hispanic34,19539.8%
Black, not Hispanic1,8732.2%
Asian, not Hispanic3,5594.1%
American Indian / Alaska Native, not Hispanic3650.4%
Native Hawaiian / Pacific Islander, not Hispanic1600.2%
Some other race, not Hispanic4410.5%
Two or more races, not Hispanic3,5144.1%

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
75,391
Citizen Voting Age Population (CVAP)
54,708

Citizen Population by Race/Ethnicity

GroupCitizensShare
Non-Hispanic42,80756.8%
Hispanic32,58643.2%
White34,89546.3%
Black1,8202.4%
Asian2,7223.6%
American Indian / Alaska Native3720.5%
Native Hawaiian / Pacific Islander1590.2%
Two or More Races3030.4%

Citizen Voting Age Population by Race/Ethnicity

GroupCVAPShare
Non-Hispanic34,90463.8%
Hispanic19,80636.2%
White29,34253.6%
Black1,9983.7%
Asian2,3574.3%
American Indian / Alaska Native1,0091.8%
Native Hawaiian / Pacific Islander1590.3%
Two or More Races740.1%

Source: Redistricting Data Hub / U.S. Census Bureau CVAP Special Tabulation (2020-2024 ACS 5-year).