Spencer leans Republican by roughly 26 points: about 37% of voters vote Democratic and 63% Republican.
About 92% of adults in Spencer typically vote, above the U.S. average of about 62%. Among adults in Spencer, ~34% vote Democratic, ~58% Republican, and ~8% don't vote. The map below shows estimated turnout by block group.
How Spencer compares
Among cities within 25 miles, Spencer leans more Republican than 4 of 41 neighbors.
Spencer runs about 13 points more Republican than Iowa as a whole.
Politics vary noticeably by neighborhood within Spencer. The northwest side is the most Republican-leaning (R+39) and the west side is the least Republican-leaning (R+22), a spread of about 16 points.
Why Spencer 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 Spencer, not a ranked or complete list of what matters most.
Spencer votes Republican even though it is densely developed (about 73%, far above the Iowa average of 16%). State and regional patterns outweigh the Democratic lean that density usually predicts here.
Preventive-care access and voter turnout
Places with strong routine preventive-care access tend to turn out at a higher rate; Spencer, IA sits in the top quarter 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 Spencer looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Spencer 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
- Fostoria, IA R+53
- Dickens, IA R+55
- Everly, IA R+56
- Royal, IA R+57
- Greenville, IA R+57
- Gillett Grove, IA R+56
- Old Town, IA R+53
- Moneta, IA R+59
- Milford, IA R+36
Cities with Similar Populations
- Maysville, KY R+35
- Commerce, CA D+33
- Rochelle, IL R+18
- Wrentham, MA D+9
- East Bethel, MN R+34
- Aransas Pass, TX R+46
- Bernalillo, NM D+10
- Pepperell, MA D+2
- Freeland, MI R+29
- Valley Falls, RI Even
Sources and methodology
Precinct-level voting records used to fit the model come from Iowa Secretary of State, 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.