Overview
- District ID
- co-sd-021
- State
- Colorado
- Chamber
- Upper chamber (state senate)
- District Code
- 021
- Land Area
- 1,373.6 sq mi
- Water Area
- 16.6 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 14 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 |
|---|
| CO District 8 | 150,756 | 89.5% | 20.9% | 9.2% |
| CO District 4 | 17,621 | 10.5% | 2.4% | 90.5% |
| CO District 6 | 36 | <0.1% | <0.1% | 0.2% |
Source: U.S. Census Bureau 2020 blocks and 2025 block equivalency files (119th Congress, 2024 state legislative plans).
Voters
- Registered Voters
- 113,119
- Active Voters
- 103,120 (91.2%)
Party Registration
| Party | Voters | Share |
|---|
| Democratic | 31,108 | 27.5% |
| Republican | 20,204 | 17.9% |
| Unaffiliated | 58,246 | 51.5% |
| Other parties | 3,561 | 3.1% |
| No party recorded | 0 | 0.0% |
Turnout by Cycle
| Cycle | General | Democratic Primary | Republican Primary |
|---|
| 2025–2026 | 28,785 (25.4%) | 0 (0.0%) | 0 (0.0%) |
| 2023–2024 | 72,303 (63.9%) | 8,433 (7.5%) | 8,617 (7.6%) |
| 2021–2022 | 49,889 (44.1%) | 6,522 (5.8%) | 5,745 (5.1%) |
| 2019–2020 | 67,985 (60.1%) | 15,398 (13.6%) | 8,434 (7.5%) |
| 2017–2018 | 45,450 (40.2%) | 7,595 (6.7%) | 4,469 (4.0%) |
| 2015–2016 | 50,874 (45.0%) | 4,617 (4.1%) | 3,164 (2.8%) |
| 2013–2014 | 31,279 (27.7%) | 3,579 (3.2%) | 3,399 (3.0%) |
| 2011–2012 | 40,463 (35.8%) | 3,141 (2.8%) | 2,202 (1.9%) |
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
- 171,126 (± 2,469)
- Median Age
- 35.0
- Median Household Income
- $93,086 (± $2,573)
- High School Graduate or Higher (age 25+)
- 84.4%
- Bachelor's Degree or Higher (age 25+)
- 24.5%
Population by Age
| Group | People | Share |
|---|
| Under 18 | 44,669 | 26.1% |
| 18 to 64 | 107,800 | 63.0% |
| 65 and over | 18,657 | 10.9% |
Population by Race and Hispanic Origin
| Group | People | Share |
|---|
| Hispanic or Latino (any race) | 85,585 | 50.0% |
| White, not Hispanic | 70,914 | 41.4% |
| Black, not Hispanic | 3,927 | 2.3% |
| Asian, not Hispanic | 3,651 | 2.1% |
| American Indian / Alaska Native, not Hispanic | 437 | 0.3% |
| Native Hawaiian / Pacific Islander, not Hispanic | 410 | 0.2% |
| Some other race, not Hispanic | 1,204 | 0.7% |
| Two or more races, not Hispanic | 4,998 | 2.9% |
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
- 154,971
- Citizen Voting Age Population (CVAP)
- 111,208
Citizen Population by Race/Ethnicity
| Group | Citizens | Share |
|---|
| Non-Hispanic | 84,205 | 54.3% |
| Hispanic | 70,766 | 45.7% |
| White | 72,312 | 46.7% |
| Black | 3,704 | 2.4% |
| Asian | 3,323 | 2.1% |
| American Indian / Alaska Native | 435 | 0.3% |
| Native Hawaiian / Pacific Islander | 370 | 0.2% |
| Two or More Races | 626 | 0.4% |
Citizen Voting Age Population by Race/Ethnicity
| Group | CVAP | Share |
|---|
| Non-Hispanic | 67,896 | 61.1% |
| Hispanic | 43,319 | 39.0% |
| White | 58,983 | 53.0% |
| Black | 3,367 | 3.0% |
| Asian | 3,839 | 3.5% |
| American Indian / Alaska Native | 1,047 | 0.9% |
| Native Hawaiian / Pacific Islander | 254 | 0.2% |
| Two or More Races | 414 | 0.4% |
Source: Redistricting Data Hub / U.S. Census Bureau CVAP Special Tabulation (2020-2024 ACS 5-year).
