Marlborough leans Democratic by roughly 20 points: about 60% of voters vote Democratic and 40% Republican.
About 60% of adults in Marlborough typically vote, near the U.S. average of about 62%. Among adults in Marlborough, ~36% vote Democratic, ~24% Republican, and ~40% don't vote. The map below shows estimated turnout by block group.
How Marlborough compares
Among cities within 25 miles, Marlborough leans more Democratic than 103 of 172 neighbors.
Marlborough runs about 39 points more Democratic than Missouri as a whole. Missouri leans Republican overall, while Marlborough is one of the few Democratic-leaning pockets.
Politics vary noticeably by neighborhood within Marlborough. The north side is the most Democratic-leaning (D+26) and the southeast side is the least Democratic-leaning (D+16), a spread of about 10 points.
Why Marlborough leans the way it does
This analysis examined 14,881 data points per city to find what predicts political lean and turnout. The items below are a few correlations that stood out for Marlborough, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 93% of residents in Marlborough live in densely developed areas, about 57 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and Marlborough sits in the top quarter (about 33%, above 80% of cities). Marlborough runs against the grain of Missouri, a Democratic-leaning pocket in a Republican-leaning state.
Walkability and Democratic lean
Places with a highly walkable street grid tend to lean Democratic; Marlborough, MO sits in the top tenth nationally on this measure. A walkable street grid does not change how people vote; it mostly reflects how urban a place is.
Why turnout in Marlborough looks the way it does
Renters vote less often than owners. About 64% of households in Marlborough rent, about 39 points above the U.S. average of 25%. Strong routine healthcare access lines up with higher turnout, and Marlborough sits in the top quarter on routine-care measures. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Grantwood Village, MO D+11
- Shrewsbury, MO D+32
- Affton, MO D+11
- Webster Groves, MO D+38
- Lakeshire, MO Even
- Wilbur Park, MO D+11
- Crestwood, MO D+19
- St. George, MO D+10
- Green Park, MO D+5
- Glendale, MO D+30
Cities with Similar Populations
- Spraberry, TX R+82
- Cairo, NY R+24
- East Williston, NY R+22
- Creal Springs, IL R+58
- Friant, CA R+40
- McLouth, KS R+49
- Thoreau, NM D+20
- South Zanesville, OH R+43
- Volant, PA R+50
- Canby, MN R+47
Sources and methodology
Precinct-level voting records used to fit the model come from Missouri Secretary of State, Elections, distributed by the Voting and Election Science Team. Demographic inputs come from the U.S. Census Bureau (ACS 5-year estimates and the 2020 Decennial Census). Health and environmental inputs come from the CDC (PLACES and the Environmental Justice Index). Land cover comes from the USGS and EPA. Election-day and lead-up weather come from PRISM 4km daily grids and the NOAA Global Historical Climatology Network. Mail-voting and election-administration patterns come from the MIT Election Lab's Survey of the Performance of American Elections. Block-group crime detail comes from CrimeGrade. Internet data and modeling support provided by ISPreports.org.
Modeling and analysis by the BestNeighborhood data science team. Full methodology and findings: political spectrum map.
Methodology reviewed by the BestNeighborhood data team. Last updated May 2026.