20155 leans slightly Democratic by roughly 6 points: about 53% of voters vote Democratic and 47% Republican.
About 85% of adults in 20155 typically vote, above the U.S. average of about 62%. Among adults in 20155, ~45% vote Democratic, ~40% Republican, and ~15% don't vote. The map below shows estimated turnout by block group.
How 20155 compares
Among zip codes within 15 miles, 20155 leans more Democratic than 11 of 27 neighbors.
Politically, 20155 sits close to the rest of Virginia.
Politics vary noticeably by block within 20155. The south side runs the most Democratic (D+11) and the southwest side runs the most Republican (Even), a spread of about 12 points.
Why 20155 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 20155, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 57% of adults in 20155 hold a bachelor's degree, about 29 points above the U.S. average of 28%. Density combined with diversity predicts Democratic voting, and non-Hispanic white share in 20155 is about 56%, about 16 points below the U.S. average of 72%.
Population density and Democratic lean
Places with high population density tend to lean Democratic; 20155, VA sits in the top quarter nationally on this measure.
Why turnout in 20155 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 20155 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 73%, about 13 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and about 97% of adults in 20155 have completed high school, above 89% 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 Virginia Department 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.