California, Louisville, KY Political Map | Democrat & Republican Areas in California

By the BestNeighborhood data science team. Last updated May 2026.

California is a Democratic stronghold. About 93% of voters here vote Democratic and 7% Republican.

 

About 49% of adults in California typically vote, below the U.S. average of about 62%. Among adults in California, ~45% vote Democratic, ~4% Republican, and ~51% don't vote. The map below shows estimated turnout by block group.

How California compares

Among neighborhoods within 5 miles, California leans more Democratic than 25 of 28 neighbors.

California runs about 117 points more Democratic than Kentucky as a whole. Kentucky leans Republican overall, while California is one of the few Democratic-leaning pockets.

Politics vary noticeably by block within California. The southwest side is the most Democratic-leaning (D+90) and the northeast side is the least Democratic-leaning (D+73), a spread of about 17 points.

Why California leans the way it does

This analysis examined 14,881 data points per neighborhood to find what predicts political lean and turnout. The items below are a few correlations that stood out for California, not a ranked or complete list of what matters most.

Dense areas vote Democratic. More than 99% of residents in California live in densely developed areas, about 64 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 54% of adults in California have never been married, above 87% of neighborhoods. California runs against the grain of Kentucky, a Democratic-leaning pocket in a Republican-leaning state.

Preventive-care access and voter turnout

Places with limited routine preventive-care access tend to turn out at a lower rate; California, Louisville, KY sits in the bottom 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 California looks the way it does

Areas with limited routine healthcare access turn out at lower rates. California is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The dental-visit rate here is about 33%, about 21 points below the Kentucky average of 54%. Low high-school completion lines up with lower turnout, and about 77% of adults in California have completed high school, below 89% of neighborhoods. High-crime urban areas turn out at lower rates, and California sits in the top 15% on a violent-crime measure. Learn more about the findings and methodology on the political spectrum map.

Sources and methodology

Precinct-level voting records used to fit the model come from Kentucky State Board 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.