37405 is a true toss-up. About 52% of voters here vote Democratic and 48% Republican.
About 68% of adults in 37405 typically vote, above the U.S. average of about 62%. Among adults in 37405, ~35% vote Democratic, ~33% Republican, and ~32% don't vote. The map below shows estimated turnout by block group.
How 37405 compares
Among zip codes within 15 miles, 37405 leans more Democratic than 20 of 30 neighbors.
37405 runs about 34 points more Democratic than Tennessee as a whole. Tennessee leans Republican overall, while 37405 is one of the few Democratic-leaning pockets.
Politics vary noticeably by block within 37405. The south side runs the most Democratic (D+26) and the northwest side runs the most Republican (R+21), a spread of about 47 points.
Why 37405 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 37405, not a ranked or complete list of what matters most.
37405 votes against the grain of Tennessee. Tennessee leans Republican overall, while 37405 runs about 34 points more Democratic.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; 37405, TN sits in the top 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 37405 looks the way it does
Turnout in 37405 sits close to the national pattern. Routine healthcare access, homeownership, education, and food security all land near their national averages here. 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 Tennessee Secretary of State, Division 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.