Turnout in 2016 was especially low in almost a thousand U.S. counties. Most of them form a geographic belt that curves from upstate New York, down along the Appalachians, across Tennessee and into the Southwest. But 2018 has brought statewide races predicted to be competitive to the heart of the low-voting belt, in West Virginia, Tennessee, Oklahoma, Texas and New Mexico. The November results will be studied for signs of closer races and greater voter involvement to come in 2020.

These maps show a turnout percentage based on two numbers for each county: ballots cast in the 2016 presidential race and the estimated population of voting-age citizens. Among the low-voting counties, those with turnout of 55 percent or less, there are some striking differences.

For example, low-voting areas span the entire urban-rural spectrum. On the map, rural areas and small towns may dominate visually. But there are far more potential votes in low-turnout metropolitan counties.