98115 is a Democratic stronghold. About 88% of voters here vote Democratic and 12% Republican.
About 80% of adults in 98115 typically vote, above the U.S. average of about 62%. Among adults in 98115, ~70% vote Democratic, ~10% Republican, and ~20% don't vote. The map below shows estimated turnout by block group.
How 98115 compares
Among zip codes within 15 miles, 98115 leans more Democratic than 60 of 65 neighbors.
98115 runs about 58 points more Democratic than Washington as a whole.
Politics vary noticeably by block within 98115. The south side is the most Democratic-leaning (D+81) and the northeast side is the least Democratic-leaning (D+68), a spread of about 13 points.
Why 98115 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 98115, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 81% of adults in 98115 hold a bachelor's degree, about 52 points above the U.S. average of 28%. Dense areas vote Democratic, and 98115 sits in the top fifth on density (about 93%, above 90% of zip codes). A high never-married share predicts Democratic voting, and about 36% of adults in 98115 have never been married, above 82% of zip codes.
Preventive-care access and voter turnout
Places with strong routine preventive-care access tend to turn out at a higher rate; 98115, WA sits in the top tenth nationally on this measure. Dental visits do not drive turnout; the rate reflects income, insurance, and healthcare access, which line up with who votes.
Why turnout in 98115 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 98115 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 76%, about 16 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and more than 99% of adults in 98115 have completed high school, above 98% 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 Washington Secretary of State, 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.