21863 leans slightly Republican by roughly 8 points: about 46% of voters vote Democratic and 54% Republican.
About 72% of adults in 21863 typically vote, above the U.S. average of about 62%. Among adults in 21863, ~33% vote Democratic, ~39% Republican, and ~28% don't vote. The map below shows estimated turnout by block group.
How 21863 compares
Among zip codes within 15 miles, 21863 leans more Republican than 2 of 9 neighbors.
21863 runs about 37 points more Republican than Maryland as a whole. Maryland leans Democratic overall, while 21863 is one of the few Republican-leaning pockets.
Politics vary noticeably by block within 21863. The west side runs the most Democratic (D+14) and the northwest side runs the most Republican (R+42), a spread of about 56 points.
Why 21863 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 21863, not a ranked or complete list of what matters most.
21863 votes against the grain of Maryland. Maryland leans Democratic overall, while 21863 runs about 37 points more Republican.
Cancer-screening access and voter turnout
Places with high colon-cancer-screening access tend to turn out at a higher rate; 21863, 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 21863 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 21863 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 61%. 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.