20721 is a Democratic stronghold. About 92% of voters here vote Democratic and 8% Republican.
About 87% of adults in 20721 typically vote, above the U.S. average of about 62%. Among adults in 20721, ~80% vote Democratic, ~7% Republican, and ~13% don't vote. The map below shows estimated turnout by block group.
How 20721 compares
Among zip codes within 15 miles, 20721 leans more Democratic than 78 of 87 neighbors.
20721 runs about 55 points more Democratic than Maryland as a whole.
Why 20721 leans the way it does
This analysis examined 14,881 data points per zip code to find what predicts political lean and turnout. The items below are a few correlations that stood out for 20721, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 57% of adults in 20721 hold a bachelor's degree, about 29 points above the U.S. average of 28%. Density combined with diversity predicts Democratic voting, and non-Hispanic white share in 20721 is about 6%, about 67 points below the U.S. average of 72%.
Preventive-care access and voter turnout
Places with strong routine preventive-care access tend to turn out at a higher rate; 20721, MD sits in the top quarter nationally on this measure. Dental visits do not drive turnout; the rate reflects income, insurance, and healthcare access, which line up with who votes.
Why turnout in 20721 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 20721 is in the top quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The dental-visit rate here is about 69%, about 9 points above the U.S. average of 60%. Homeowners vote more often than renters, and about 89% of households in 20721 own their home, above 84% of zip codes. High high-school completion lines up with higher turnout, and about 97% of adults in 20721 have completed high school, above 87% of zip codes. Learn more about the findings and methodology on the political spectrum map.
Nearby Zip Codes
Zip Codes with Similar Populations
Sources and methodology
Precinct-level voting records used to fit the model come from Maryland State Board of 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.