Crystal Lake leans heavily Republican by roughly 46 points: about 27% of voters vote Democratic and 73% Republican.
About 89% of adults in Crystal Lake typically vote, above the U.S. average of about 62%. Among adults in Crystal Lake, ~24% vote Democratic, ~65% Republican, and ~11% don't vote. The map below shows estimated turnout by block group.
How Crystal Lake compares
Among cities within 25 miles, Crystal Lake leans more Republican than 19 of 37 neighbors.
Crystal Lake runs about 33 points more Republican than Iowa as a whole.
Why Crystal Lake leans the way it does
Density, race composition, education, and family structure all sit close to their national averages in Crystal Lake. The lean here lands roughly where demographic data alone would predict.
Population density and Republican lean
Places with low population density tend to lean Republican; Crystal Lake, IA sits in the bottom quarter nationally on this measure.
Why turnout in Crystal Lake looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Crystal Lake 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%. Homeowners vote more often than renters, and about 90% of households in Crystal Lake own their home, above 81% of cities. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Hayfield, IA R+53
- Woden, IA R+50
- Forest City, IA R+22
- Duncan, IA R+52
- Britt, IA R+37
- Hutchins, IA R+51
- Leland, IA R+39
- Thompson, IA R+37
- Miller, IA R+45
- Titonka, IA R+55
Cities with Similar Populations
- Minersville, WI R+7
- Marengo, VA R+25
- Galvin, WA R+31
- Pleasantville, WI R+30
- Trent, OR R+17
- Solgohachia, AR R+61
- Lacey, OK R+74
- Trenton, KS R+60
- Kincheon, AL R+77
- Richview, IL R+64
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.