21784 leans slightly Republican by roughly 12 points: about 44% of voters vote Democratic and 56% Republican.
About 91% of adults in 21784 typically vote, above the U.S. average of about 62%. Among adults in 21784, ~40% vote Democratic, ~51% Republican, and ~9% don't vote. The map below shows estimated turnout by block group.
How 21784 compares
Among zip codes within 15 miles, 21784 leans more Republican than 21 of 26 neighbors.
21784 runs about 40 points more Republican than Maryland as a whole. Maryland leans Democratic overall, while 21784 is one of the few Republican-leaning pockets.
Politics vary noticeably by block within 21784. The south side runs the most Democratic (D+3) and the west side runs the most Republican (R+27), a spread of about 30 points.
Why 21784 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 21784, not a ranked or complete list of what matters most.
21784 votes against the grain of Maryland. Maryland leans Democratic overall, while 21784 runs about 40 points more Republican. A high family-household share predicts Republican voting, and about 80% of households in 21784 are family households, above 92% of zip codes.
High-school completion, uninsured rate, and voter turnout
Places that combine high-school-completion-heavy adults and a low uninsured rate tend to turn out at a higher rate, as 21784, MD does.
Why turnout in 21784 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 21784 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 71%, about 11 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and about 96% of adults in 21784 have completed high school, above 84% 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.