Missouri State Senate District 21

State Legislative District Profile (Upper Chamber)

Overview

District ID
mo-sd-021
State
Missouri
Chamber
Upper chamber (state senate)
District Code
021
Land Area
3,266 sq mi
Water Area
48.3 sq mi

Boundary

Boundary of Missouri State Senate District 21

Boundary as GeoJSON

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

Counties

CountyOverlapShare of district landShare of county land
Saline County755.51 sq mi23.1%100.0%
Lafayette County628.28 sq mi19.2%100.0%
Ray County568.97 sq mi17.4%100.0%
Cooper County564.75 sq mi17.3%100.0%
Howard County463.80 sq mi14.2%100.0%
Clay County284.63 sq mi8.7%71.6%

Showing all 6 counties

Places

PlaceOverlapShare of district landShare of place land
Liberty city28.83 sq mi0.9%97.2%
Smithville city15.95 sq mi0.5%98.7%
Kearney city13.33 sq mi0.4%100.0%
Excelsior Springs city10.85 sq mi0.3%100.0%
Marshall city10.12 sq mi0.3%100.0%
Boonville city7.69 sq mi0.2%92.9%
Richmond city6.15 sq mi0.2%100.0%
Lexington city5.23 sq mi0.2%100.0%
Odessa city4.10 sq mi0.1%99.9%
Higginsville city3.77 sq mi0.1%100.0%
Lawson city2.96 sq mi0.1%100.0%
Wood Heights city2.28 sq mi0.1%100.0%
Prathersville village2.25 sq mi0.1%100.0%
Fayette city2.22 sq mi0.1%100.0%
Concordia city1.83 sq mi0.1%100.0%
Mosby city1.81 sq mi0.1%97.3%
Napoleon city1.75 sq mi0.1%100.0%
Sweet Springs city1.66 sq mi0.1%100.0%
Slater city1.45 sq mi<0.1%100.0%
Vibbard CDP1.40 sq mi<0.1%100.0%
Orrick city1.33 sq mi<0.1%93.1%
New Franklin city1.32 sq mi<0.1%100.0%
Glasgow city1.27 sq mi<0.1%94.2%
Waverly city1.26 sq mi<0.1%100.0%
Missouri City city1.10 sq mi<0.1%100.0%

Showing top 25 of 65 places

Overlapping Congressional Districts

Congressional districtPopulation in bothShare of this district's populationShare of the congressional district's populationShare of this district's land
MO District 6100,49154.6%13.1%26.1%
MO District 466,46836.1%8.6%56.6%
MO District 317,1039.3%2.2%17.3%

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

Voters

Registered Voters
131,304
Active Voters
121,396 (92.5%)

Party Registration

PartyVotersShare
Democratic1,4921.1%
Republican3,6542.8%
Unaffiliated29,85022.7%
Other parties1540.1%
No party recorded96,15473.2%

Turnout by Cycle

CycleGeneralDemocratic PrimaryRepublican Primary
2025–202617,246 (13.1%)0 (0.0%)0 (0.0%)
2023–202496,158 (73.2%)0 (0.0%)0 (0.0%)
2021–202266,473 (50.6%)0 (0.0%)0 (0.0%)
2019–202087,262 (66.5%)0 (0.0%)0 (0.0%)
2017–201867,677 (51.5%)0 (0.0%)0 (0.0%)
2015–201673,730 (56.2%)0 (0.0%)0 (0.0%)
2013–201441,995 (32.0%)0 (0.0%)0 (0.0%)
2011–201264,256 (48.9%)0 (0.0%)0 (0.0%)

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 01/02/2026. These are registered voters, separate from the Census population figures. Counts under 10 are suppressed and shown as "<10".

Demographics

Total Population
185,602 (± 566)
Median Age
39.6
Median Household Income
$80,897 (± $2,377)
High School Graduate or Higher (age 25+)
91.8%
Bachelor's Degree or Higher (age 25+)
28.5%

Population by Age

GroupPeopleShare
Under 1842,65323.0%
18 to 64109,07458.8%
65 and over33,87518.3%

Population by Race and Hispanic Origin

GroupPeopleShare
Hispanic or Latino (any race)8,5454.6%
White, not Hispanic161,84387.2%
Black, not Hispanic5,2622.8%
Asian, not Hispanic9970.5%
American Indian / Alaska Native, not Hispanic4310.2%
Native Hawaiian / Pacific Islander, not Hispanic3560.2%
Some other race, not Hispanic6540.4%
Two or more races, not Hispanic7,5144.0%

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
183,740
Citizen Voting Age Population (CVAP)
141,327

Citizen Population by Race/Ethnicity

GroupCitizensShare
Non-Hispanic176,23695.9%
Hispanic7,5014.1%
White163,92789.2%
Black5,4973.0%
Asian7030.4%
American Indian / Alaska Native4470.2%
Native Hawaiian / Pacific Islander2200.1%
Two or More Races5350.3%

Citizen Voting Age Population by Race/Ethnicity

GroupCVAPShare
Non-Hispanic136,53796.6%
Hispanic4,7853.4%
White127,78190.4%
Black5,8374.1%
Asian8170.6%
American Indian / Alaska Native1,5801.1%
Native Hawaiian / Pacific Islander1470.1%
Two or More Races3870.3%

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