The spin wars are under way in Ohio.

Both campaigns released memos Thursday claiming an advantage among early voters in the Buckeye State.

Republican Mitt Romney’s campaign said Republicans are outperforming voter-registration levels in seven of Ohio’s largest counties in absentee-ballot requests and early voting. Overall, according to the campaign, registered Republicans represent 19 percent of all registered voters but account for 29 percent of those who have requested absentee ballots or have voted early.

Not to be outdone, President Obama's campaign served up own memo late Tuesday with a series of statistics claiming that early voting favors him. The memo, from national field director Jeremy Bird, cited four public polls, all of which give Obama a double-digit lead among early voters and absentee voters.

The most credible of those four, a Wall Street Journal/NBC survey, found that Obama leads by 26 points (63/37) among those who have voted already.

Furthermore, Bird said, four in five Ohioans who registered to vote in 2012 are either women, younger than 30 or African-american or Latino . All, Bird said, are groups that “strongly favor” Obama. And two-thirds of those who have voted live in counties that Obama won four years ago.

So who’s right? According to Michael McDonald, a George Mason University professor who studies voting trends, the Republican claims are not quite right.

“Republicans have crowed that the number of Ohio-registered Republicans voting early has increased from 2008,” McDonald wrote last week. “The problem with this assertion is that Ohio does not have party registration. ‘Party’ in Ohio is a record of the last party primary a voter participated in. Naturally, with only a contested 2012 Republican presidential primary, the number of ‘registered Republicans’ in the state increased.”