Terrebonne Parish leans heavily Republican by roughly 42 points: about 29% of voters vote Democratic and 71% Republican.
About 64% of adults in Terrebonne Parish typically vote, near the U.S. average of about 62%. Among adults in Terrebonne Parish, ~19% vote Democratic, ~45% Republican, and ~36% don't vote. The map below shows estimated turnout by block group.
How Terrebonne Parish compares
Among counties within 50 miles, Terrebonne Parish leans more Republican than 8 of 9 neighbors.
Terrebonne Parish runs about 20 points more Republican than Louisiana as a whole.
Politics vary noticeably by city within Terrebonne Parish. The southwest side is the most Republican-leaning (R+77) and the east side is the least Republican-leaning (R+31), a spread of about 46 points.
Why Terrebonne Parish 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 Terrebonne Parish, not a ranked or complete list of what matters most.
Car-dependent areas vote Republican. About 84% of residents in Terrebonne Parish drive to work alone, about 10 points above the U.S. average of 74%. A high family-household share predicts Republican voting, and about 69% of households in Terrebonne Parish are family households, above 77% of counties.
Park access and Republican lean
Places with low park coverage tend to lean Republican; Terrebonne Parish, LA sits below the national average on this measure. Park access does not change how people vote; it tends to track denser, higher-income areas.
Why turnout in Terrebonne Parish looks the way it does
Turnout in Terrebonne Parish 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
- Lafourche Parish, LA R+55
- St. James Parish, LA D+3
- Assumption Parish, LA R+30
- St. Charles Parish, LA R+25
- St. John the Baptist Parish, LA D+27
- St. Mary Parish, LA R+23
- Jefferson Parish, LA D+4
- Ascension Parish, LA R+32
- Orleans Parish, LA D+63
- Plaquemines Parish, LA R+27
Counties with Similar Populations
- Warren County, NJ R+16
- LaSalle County, IL R+21
- Pennington County, SD R+28
- Hanover County, VA R+21
- Eaton County, MI R+8
- Madison County, MS R+5
- Bartow County, GA R+46
- Miami County, OH R+42
- Bradley County, TN R+48
- Mercer County, PA R+27
Sources and methodology
Precinct-level voting records used to fit the model come from Louisiana 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.