Multnomah County is a Democratic stronghold. About 76% of voters here vote Democratic and 24% Republican.
About 71% of adults in Multnomah County typically vote, above the U.S. average of about 62%. Among adults in Multnomah County, ~54% vote Democratic, ~17% Republican, and ~29% don't vote. The map below shows estimated turnout by block group.
How Multnomah County compares
Among counties within 50 miles, Multnomah County is the most Democratic-leaning.
Multnomah County runs about 38 points more Democratic than Oregon as a whole.
Politics vary noticeably by city within Multnomah County. The south side is the most Democratic-leaning (D+75) and the southeast side is the least Democratic-leaning (D+24), a spread of about 52 points.
Why Multnomah County leans the way it does
This analysis examined 14,881 data points per county to find what predicts political lean and turnout. The items below are a few correlations that stood out for Multnomah County, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 94% of residents in Multnomah County live in densely developed areas, about 58 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and Multnomah County sits in the top quarter (about 48%, above 96% of counties). A high never-married share predicts Democratic voting, and about 41% of adults in Multnomah County have never been married, above 94% of counties.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; Multnomah County, OR sits in the top tenth 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 Multnomah County looks the way it does
Turnout in Multnomah County 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 Counties
- Clackamas County, OR D+13
- Clark County, WA D+7
- Washington County, OR D+32
- Columbia County, OR R+18
- Yamhill County, OR R+5
- Skamania County, WA R+13
- Marion County, OR D+3
- Cowlitz County, WA R+18
- Hood River County, OR D+24
- Polk County, OR R+4
Counties with Similar Populations
- Essex County, MA D+18
- Fort Bend County, TX D+6
- Snohomish County, WA D+10
- Hamilton County, OH D+21
- Suffolk County, MA D+53
- Oklahoma County, OK D+6
- Ventura County, CA D+16
- Jefferson County, KY D+20
- San Joaquin County, CA D+4
- Baltimore County, MD D+28
All Local Stats
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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.