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Bracing for a long night, President Obama today warned that if the race is close, a clear winner in the presidential election may not be determined until tomorrow morning.

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"One way or another we're going to have a winner," he told ABC's Washington, D.C., affiliate WJLA. "If it's close, it may spill into the morning, but I'm pretty confident that we'll end up having a president-elect come Wednesday."

Obama expressed confidence that "the votes are there for us to win" as he urged Americans to get to the polls. "I just hope people don't sit on the sidelines. The stakes are so high," he said, in one of 10 TV interviews he did this morning in a final push to get out the vote.

"I'm confident that if we see good turnout across the country that I potentially have the privilege of serving the American people for another four years," he continued.

Looking back on his final campaign, the president was asked if there was anything he would have done differently. "Overall, we've run a race that I can be proud of. Obviously, I should have probably had a few more cups of coffee before the first debate," he joked. "But other than that, I feel very good about the work we've done."

Tune in to ABCNews.com for livestreaming coverage of Election 2012. The Election Night event begins at 7 p.m.