21015 leans slightly Republican by roughly 10 points: about 45% of voters vote Democratic and 55% Republican.
About 89% of adults in 21015 typically vote, above the U.S. average of about 62%. Among adults in 21015, ~40% vote Democratic, ~49% Republican, and ~11% don't vote. The map below shows estimated turnout by block group.
How 21015 compares
Among zip codes within 15 miles, 21015 leans more Republican than 15 of 33 neighbors.
21015 runs about 38 points more Republican than Maryland as a whole. Maryland leans Democratic overall, while 21015 is one of the few Republican-leaning pockets.
Politics vary noticeably by block within 21015. The north side is the most split-leaning (R+21) and the southwest side is the least split-leaning (Even), a spread of about 20 points.
Why 21015 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 21015, not a ranked or complete list of what matters most.
21015 votes against the grain of Maryland. Maryland leans Democratic overall, while 21015 runs about 38 points more Republican. Dense places usually vote Democratic, but 21015 runs against that pattern. A high family-household share predicts Republican voting, and about 79% of households in 21015 are family households, above 90% of zip codes.
Cancer-screening access and voter turnout
Places with high colon-cancer-screening access tend to turn out at a higher rate; 21015, MD sits in the top quarter nationally on this measure. Cancer screening does not drive turnout; it reflects income, insurance, and healthcare access.
Why turnout in 21015 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 21015 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 70%, about 10 points above the U.S. average of 60%. Homeowners vote more often than renters, and about 89% of households in 21015 own their home, above 84% of zip codes. High high-school completion lines up with higher turnout, and about 97% of adults in 21015 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.