The Obama and Romney campaigns may be gearing up for a very late night, with one Obama campaign adviser predicting that in Florida alone, "they'll be counting until 2 a.m."
The Obama adviser said signs suggest the race is quite tight, though the campaign claimed to be "holding strong" in key battlegrounds like Ohio, Pennsylvania and Wisconsin.
The adviser also said turnout among black voters in Virginia was better than expected, suggesting that could be a problem for Mitt Romney.
Republican operatives in Virginia, though, predicted a razor-thin victory for their candidate in the state.
Sources there said turnout in virtually all counties across Virginia is exceedingly high for both parties -- "insane," as one source put it.
In Ohio, Secretary of State Jon Husted predicted turnout would be near that of 2008, when more than 5.7 million voted. Husted said this year up to 5.8 million could cast ballots.
Obama, though, said in an interview with a TV station in Washington, D.C., that he expected "we'll end up having a president-elect come Wednesday."
Fox News' Ed Henry, James Rosen and Steve Brown contributed to this report.
