21523 is a Republican stronghold. About 17% of voters here vote Democratic and 83% Republican.
About 90% of adults in 21523 typically vote, above the U.S. average of about 62%. Among adults in 21523, ~15% vote Democratic, ~75% Republican, and ~10% don't vote. The map below shows estimated turnout by block group.
How 21523 compares
Among zip codes within 15 miles, 21523 leans more Republican than 12 of 17 neighbors.
21523 runs about 95 points more Republican than Maryland as a whole. Maryland leans Democratic overall, while 21523 is one of the few Republican-leaning pockets.
Why 21523 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 21523, not a ranked or complete list of what matters most.
21523 votes against the grain of Maryland. Maryland leans Democratic overall, while 21523 runs about 95 points more Republican.
Paved land cover and Republican lean
Places with little paved surface tend to lean Republican; 21523, MD sits in the bottom quarter nationally on this measure. Paved ground does not change how people vote; it mostly reflects how urban and built-up a place is.
Why turnout in 21523 looks the way it does
Homeowners vote more often than renters. About 94% of households in 21523 own their home, about 17 points above the Maryland average of 77%. 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.