Voting in Cuyahoga County

Voters fill out their ballots earlier this month at the Cuyahoga County Board of Elections.

(Marvin Fong, The Plain Dealer)

New voter registrations make up a larger share of all voters in the counties shaded in dark green. The map shows the percent of 2016 registrations among all registered voters for each county.

CLEVELAND, Ohio - Ohio counties where Donald Trump ran strongest in the March primary are among the weakest in new voter registrations this year.

Many factors could be involved, such as population changes, or how often people in those places move.

But lagging new voter registration in key Trump country in eastern and southern Ohio could raise questions about a theory that Trump's campaign has excited people to come out to vote for the first time in years.

If he is going to attract new voters for the Republican Party, the data suggest they will more likely be former Democratic voters or independents rather than those new to the election process.

analyzed voter registration data from the Secretary of State and matched it to March primary results, finding that:

In the 32 counties where Trump defeated Ohio Gov. John Kasich, 113,968 voters registered this year by the Oct. 11 deadline. They make up 9 percent of the potential electorate in those counties.

In the other 56 counties, 839,907 voters registered this year, making up 13 percent of all registered voters in those places.

Though Donald Trump lost the 2016 Ohio Republican Primary to Gov. John Kasich, Trump won the 32 counties shown in red on this map.

Athens County, home to Ohio University and a place where Bernie Sanders ran the strongest in the Democratic Primary, leads with 22.8 percent newly registered voters this year.



Key to Hillary Clinton's campaign will be both getting Sanders supporters to the polls and to vote for her this fall.



Close behind is Cuyahoga County, where the 201,269 voters registered this year make up 22.6 percent of all registered voters. It is key Democratic territory. Four years ago, Barack Obama won bigger in Cuyahoga than any other county in Ohio.



Joshua Eck, spokesman for the Secretary of State, said newly registered voters likely fall into two groups - people registering for the first time, or people who have moved into a county from either elsewhere in Ohio or out of state.



This is why places where large shares of the population are college students, such as Athens County with Ohio University and Wood County with Bowling Green State University, tend to have higher numbers of fresh registrations.



Eck said it is also possible that some people moving within a county mistakenly show up in the records as newly registered voters.



Rich Exner, data analysis editor for cleveland.com, writes about numbers on a variety of topics. Follow on Twitter @RichExner or see previous stories at cleveland.com/datacentral.



Eastern and southern Ohio battlefield for Cinton and Trump