The Cleveland Plain Dealer is reporting that 25% of registered voters in northeastern Ohio have already voted early.
The Columbus Dispatch is estimating that the early votes have gone to Obama by a 56% - 42% margin.
With a little over 8 million registered voters, that would mean around 2 million Ohioans have already voted and have give Obama a lead of around 280,000 votes before the polls opened today.
If turnout runs around 75%, there will be about 4 million votes cast today. That would mean McCain has to win today by a 53% - 46% margin across the entire state.
I'll be updating the Ohio Voting Results projecting the final vote totals this evening as they come in.