Grass Valley is a Republican stronghold. About 18% of voters here vote Democratic and 82% Republican.
About 60% of adults in Grass Valley typically vote, near the U.S. average of about 62%. Among adults in Grass Valley, ~11% vote Democratic, ~49% Republican, and ~40% don't vote. The map below shows estimated turnout by block group.
How Grass Valley compares
Among cities within 25 miles, Grass Valley is the most Republican-leaning.
Grass Valley runs about 77 points more Republican than Oregon as a whole. Oregon leans Democratic overall, while Grass Valley is one of the few Republican-leaning pockets.
Why Grass Valley 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 Grass Valley, not a ranked or complete list of what matters most.
Grass Valley votes against the grain of Oregon. Oregon leans Democratic overall, while Grass Valley runs about 77 points more Republican. Rural areas vote Republican, and Grass Valley sits in the bottom quarter on density (about 2%, below 95% of cities).
Population density and Republican lean
Places with low population density tend to lean Republican; Grass Valley, OR sits in the bottom tenth nationally on this measure.
Why turnout in Grass Valley looks the way it does
Renters vote less often than owners. About 37% of households in Grass Valley rent, about 12 points above the U.S. average of 25%. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Moro, OR R+62
- Kent, OR R+54
- Wasco, OR R+56
- Shaniko, OR R+51
- Dufur, OR R+45
- Maupin, OR R+47
- Wishram, WA R+39
- Friend, OR R+44
- Rufus, OR R+56
- Tygh Valley, OR R+42
Cities with Similar Populations
- Port Gamble, WA D+4
- Fatio, FL R+63
- McClures Bend, TN R+66
- Northboro, IA R+54
- Black Springs, AR R+73
- McGrath, AK D+15
- Sterling Center, MN R+42
- Rolling Meadows, TX R+62
- Lone Pine, LA R+70
- Lincolnville, PA R+59
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.