21108 leans slightly Democratic by roughly 10 points: about 55% of voters vote Democratic and 45% Republican.
About 87% of adults in 21108 typically vote, above the U.S. average of about 62%. Among adults in 21108, ~48% vote Democratic, ~39% Republican, and ~13% don't vote. The map below shows estimated turnout by block group.
How 21108 compares
Among zip codes within 15 miles, 21108 leans more Democratic than 11 of 59 neighbors.
21108 runs about 19 points more Republican than Maryland as a whole.
Politics vary noticeably by block within 21108. The north side runs the most Democratic (D+32) and the southwest side runs the most Republican (R+5), a spread of about 37 points.
Why 21108 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 21108, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 53% of adults in 21108 hold a bachelor's degree, about 25 points above the U.S. average of 28%. Dense areas vote Democratic, and 21108 sits in the top fifth on density (about 78%, above 82% of zip codes).
Preventive-care access and voter turnout
Places with strong routine preventive-care access tend to turn out at a higher rate; 21108, MD sits in the top tenth 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 21108 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 21108 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 72%, about 12 points above the U.S. average of 60%. Homeowners vote more often than renters, and about 89% of households in 21108 own their home, above 83% of zip codes. High high-school completion lines up with higher turnout, and about 97% of adults in 21108 have completed high school, above 88% 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.