03603 leans heavily Republican by roughly 32 points: about 34% of voters vote Democratic and 66% Republican. These figures are model estimates: New Hampshire did not have precinct-level voting records available for training, so the numbers above come from demographic and health features rather than local ground truth.
About 80% of adults in 03603 typically vote, above the U.S. average of about 62%. Among adults in 03603, ~27% vote Democratic, ~53% Republican, and ~20% don't vote. The map below shows estimated turnout by block group.
How 03603 compares
Among zip codes within 15 miles, 03603 is the most Republican-leaning.
03603 runs about 35 points more Republican than New Hampshire as a whole. New Hampshire is roughly evenly split, and 03603 sits clearly on the Republican side.
Why 03603 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 03603, not a ranked or complete list of what matters most.
Areas with low college attainment vote Republican. About 13% of adults in 03603 hold a bachelor's degree, about 26 points below the New Hampshire average of 39%. 03603 runs against the grain of New Hampshire, a Republican-leaning outlier in a roughly evenly split state.
High-school completion and voter turnout
Places with high-school-completion-heavy adults tend to turn out at a higher rate; 03603, NH sits in the top quarter nationally on this measure.
Why turnout in 03603 looks the way it does
Areas with high high-school completion turn out at higher rates. About 96% of adults in 03603 have completed high school, about 7 points above the U.S. average of 90%. 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 New Hampshire Secretary of State, Elections Division, 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. NH did not have precinct-level voting records available for training, so the figures here come from extrapolation across demographic, health, and land-use features rather than local ground truth. Full methodology and findings: political spectrum map.
Methodology reviewed by the BestNeighborhood data team. Last updated May 2026.