19966 leans slightly Republican by roughly 14 points: about 43% of voters vote Democratic and 57% Republican.
About 80% of adults in 19966 typically vote, above the U.S. average of about 62%. Among adults in 19966, ~35% vote Democratic, ~46% Republican, and ~19% don't vote. The map below shows estimated turnout by block group.
How 19966 compares
Among zip codes within 15 miles, 19966 leans more Republican than 8 of 15 neighbors.
19966 runs about 28 points more Republican than Delaware as a whole. Delaware leans Democratic overall, while 19966 is one of the few Republican-leaning pockets.
Politics vary noticeably by block within 19966. The south side runs the most Democratic (D+12) and the northwest side runs the most Republican (R+42), a spread of about 53 points.
Why 19966 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 19966, not a ranked or complete list of what matters most.
19966 votes against the grain of Delaware. Delaware leans Democratic overall, while 19966 runs about 28 points more Republican.
Park access and Republican lean
Places with low park coverage tend to lean Republican; 19966, DE sits below the national average on this measure. Park access does not change how people vote; it tends to track denser, higher-income areas.
Why turnout in 19966 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 19966 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 62%, compared to around 68% in nearby 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 Delaware 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.