Portland, OR Political Map | Democrat & Republican Areas in Portland

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

Portland leans Democratic by roughly 26 points: about 63% of voters vote Democratic and 37% Republican.

 

About 76% of adults in the Portland area typically vote, above the U.S. average of about 62%. Among adults in the Portland area, ~48% vote Democratic, ~28% Republican, and ~24% don't vote. The map below shows estimated turnout by block group.

How Portland compares

Among cities within 25 miles, Portland leans more Democratic than 68 of 87 neighbors.

Portland runs about 12 points more Democratic than Oregon as a whole.

Politics vary noticeably by neighborhood within Portland. The west side runs the most Democratic (D+39) and the south side runs the most Republican (R+4), a spread of about 43 points.

Why Portland leans the way it does

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

Dense areas vote Democratic. About 82% of residents in the Portland area live in densely developed areas, about 46 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and Portland sits in the top quarter (about 43%, above 89% of cities). A high never-married share predicts Democratic voting, and about 33% of adults in the Portland area have never been married, above 82% of cities.

Population density and Democratic lean

Places with high population density tend to lean Democratic; Portland, OR sits in the top tenth nationally on this measure.

Why turnout in Portland looks the way it does

Turnout in the Portland area 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.

Sources and methodology

Precinct-level voting records used to fit the model come from Oregon 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. Full methodology and findings: political spectrum map.

Methodology reviewed by the BestNeighborhood data team. Last updated May 2026.