Polls close in three states, including all-important Ohio (18 electoral votes) and competitive North Carolina (15).
If Ohio is particularly close, and polls suggest it might be, there's a chance the outcome there won't be known until after Election Day, and the presidency could hinge on it. In the last several elections, between 2 percent and 3 percent of the state's votes came from provisional ballots, which aren't counted until later. In 2004, after a long, tense night counting votes, the presidential race wasn't decided until 11 a.m. the next day, when Democrat John Kerry called President George Bush to concede Ohio and the presidency.
Romney desperately needs Ohio; no Republican has won the presidency without it. Without Ohio, Romney would need victories in nearly all the remaining up-for-grabs states and he'd have to pick off key states now leaning Obama's way, such as Wisconsin and Iowa. Obama has more work-arounds than Romney if he can't claim Ohio.
In North Carolina, the most conservative of the hotly contested states, Romney appeared to have the late edge in polling. Obama, who narrowly won the state in 2008, has paid less attention to it recently. An Obama victory there could point to broader troubles for Romney.
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