Obama Casts Early Vote and Reminds Dems of 2000 Recount Obama casts own ballot as campaigns fight to stir early voters.

Oct. 25, 2012 -- President Obama took a break from a marathon blitz of swing states today to cast an early ballot in his home town of Chicago, making him the first sitting president to vote in-person before Election Day.

"I can't tell you who I'm voting for," he told supporters at a rally in Tampa, Fla., earlier in the day. "It's a secret ballot. But Michelle says she voted for me."

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Obama hopes his early voting will set an example for supporters to follow. The campaign is committing an unprecedented amount of rhetorical and tactical resources to getting votes banked before polls officially open in 12 days.

A new ad released today is meant to remind Democrats how close an election can be by looking back at the 2000 Florida recount, which George W. Bush won by 537 votes. Florida gave Bush the electoral votes he needed to win the presidency.

"So this year if you're thinking that your vote doesn't count, that it won't matter," a narrator says. "Well, back then there were probably 537 people who felt the same way. Make your voice heard."

In Tampa's Hillsborough County, the largest in Florida's "I-4 Corridor," the campaign has been pushing a "Vote Now" initiative since Sept. 22.

In Ohio, where early voting is underway, the Democrats are using political rallies as a way to bring voters together and bundle them off to the polls.

"Two weeks from today Americans all across the country will step into the voting booth," Obama said at a rally in Dayton earlier this week. "But here in Ohio, you can vote early. Here in Ohio, you can vote right after this event."

The Romney campaign has taken a different tack.

"Republican voters traditionally vote on Election Day, but we have an aggressive ground game in place to turn out 'low propensity early voters' who don't always make it to the polls," spokeswoman Sarah Pompei told ABC News.

Republicans are expressing confidence the early numbers, when compared to Obama's dominant 2008 showing, are swinging in their direction.

The Obama campaign, however, believes it is again running up a commanding lead in the early voting, especially in Ohio. Romney's staff doesn't deny there's a gap, but insists it's not nearly as large as Democrats say. The question is whether it's a deficit that Romney can make up on Nov. 6.

Right now, according to a Time Magazine poll, both candidates are sitting at 45 percent among respondents who have yet to submit their vote.

Republicans disputed the Time survey by noting that it reports a 53-38 lead for Romney among independent voters. "That's just not possible," the campaign said in a memo released this afternoon. "Write it down – if Mitt Romney wins independent voters by 15 points in Ohio, he'll be the next president of the United States."

Romney concentrated his campaign in Ohio today, holding rallies in three locations where he promised "big change" and played up momentum he said has been building since the first debate.

"The Obama campaign doesn't have a plan," Romney told supporters in Cincinnati. "The Obama campaign is slipping because he's talking about smaller and smaller things despite the fact that America has such huge challenges and that this is such an opportunity for America, and that's why on Nov. 6 I'm counting on Ohio to vote for big change."

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Elsewhere on the trail, vice presidential nominee Paul Ryan's rally in Bristol, Va., was visited by a plane dragging a sign that read, "Romney's GOP: Wrong on Rape and Women."

The message, sponsored by liberal activists MoveOn.Org, is part of an effort to stoke outrage over comments made by the Republican Indiana Senate candidate Richard Mourdock. During a debate Tuesday, "I've struggled with it myself for a long time, but I came to realize that life is that gift from God. And, I think, even when life begins in that horrible situation of rape, that it is something that God intended to happen."

Mourdock has since said his words were "mistook and twisted." Romney, who cut a TV and web ad supporting him in the days before the debate, has distanced himself from the Indiana state treasurer, but not asked his campaign to take down the video.

Mary Bruce contributed to this report