Tualatin leans heavily Democratic by roughly 32 points: about 66% of voters vote Democratic and 34% Republican.
About 76% of adults in Tualatin typically vote, above the U.S. average of about 62%. Among adults in Tualatin, ~50% vote Democratic, ~26% Republican, and ~24% don't vote. The map below shows estimated turnout by block group.
How Tualatin compares
Among cities within 25 miles, Tualatin leans more Democratic than 91 of 103 neighbors.
Tualatin runs about 18 points more Democratic than Oregon as a whole.
Politics vary noticeably by neighborhood within Tualatin. The southwest side is the most Democratic-leaning (D+38) and the southeast side is the least Democratic-leaning (D+12), a spread of about 26 points.
Why Tualatin 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 Tualatin, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 89% of residents in Tualatin live in densely developed areas, about 52 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and Tualatin sits in the top quarter (about 47%, above 92% of cities). A high never-married share predicts Democratic voting, and about 31% of adults in Tualatin have never been married, above 78% of cities.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; Tualatin, 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 Tualatin looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Tualatin is in the top quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The dental-visit rate here is about 68%, about 8 points above the U.S. average of 60%. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Durham, OR D+36
- Rivergrove, OR D+43
- King City, OR D+27
- Tigard, OR D+40
- Lake Oswego, OR D+45
- Bull Mountain, OR D+29
- Sherwood, OR D+14
- Wilsonville, OR D+21
- West Linn, OR D+33
- Oak Grove, OR D+37
Cities with Similar Populations
- Selma, CA Even
- Schererville, IN R+5
- Marshalltown, IA R+9
- Windsor, CA D+30
- Roslindale, MA D+61
- Fridley, MN D+23
- Magna, UT R+6
- Waynesboro, VA R+18
- Collinsville, IL Even
- Scaggsville, MD D+44
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.