President Barack Obama speaks to supporters during a campaign rally on September 22, 2012 in Milwaukee, Wisconsin. (Photo by Scott Olson/Getty Images)

CHARLOTTE, N.C. — When Michelle Obama recently visited North Carolina Central University, a historically black college in Durham, she didn’t just urge people to vote, but told them exactly when.

“If you vote early, you get that out of the way, then you can spend Election Day working to get other people to the polls,” she said.

Voting on Election Day sometimes has complications, particularly long lines. So in key battleground states, Team Obama is aggressively organizing to get its supporters to use early voting programs. When early voting starts in Ohio on Oct. 2, Michelle Obama will be in Cincinnati in person, carrying the same message she did in North Carolina. Thousands of black voters and others are expected to cast ballots in Florida from Oct. 27 to Nov. 3, the early voting period there.

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Romney campaign officials are also making a strong push on the early vote, and officials from both parties said that about a third of the electorate overall and perhaps as many as half in key battleground states will vote before Nov. 6,  the official election day.

Viewing early voting as critical, the Obama campaign has fought Republican-led efforts to reduce it. In Ohio, the campaign won a lawsuit it filed against a provision that would have cut off early voting in the three days before the election. But in Florida on Monday, a federal judge upheld a new law that cuts the number of early voting days from 14 to 8 and eliminates voting on the Sunday before the election, when churches and campaigns organize to take people directly from Sunday services to vote.

Team Obama still thinks its candidate has the advantage in the early vote and is doing everything it can to maintain it. By locking in as many votes as possible now, officials say the campaign can then focus its resources on getting those who may be less likely to vote to the polls on Election Day.

Early voting is also a way to counter and diminish the effect of the expected, heavily-funded GOP ad attacks in the final weeks before the election.

“We’ve kept a sustained conversation going with our volunteers, supporters and undecided voters in battleground states since 2007 – that’s a significant advantage that can’t be duplicated in the final weeks and months,” said Clo Ewing, an Obama campaign spokesman.

And with states having a patchwork of different deadlines and changing rules for early in-person and absentee voting, the emphasis is on voter education.

“We are making sure that people exercise their right to vote, encourage them to do it as early as they can, and are asking them to spread the word with their peers and their neighbors,” said Ewing.

The campaign’s website is a state-specific resource for voting information. (Other groups using technology to inform and educate the public on voting changes include the nonprofit Pew Charitable Trusts, partnering with campaign managers, elections boards and others for its Voting Information Project just in time for Sept. 25, National Voter Registration Day.)

Republicans are consolidating their get out the vote effort in states where the party thinks it will be most effective. For example, reliably red Georgia, South Carolina, and Tennessee have pledged to send resources and volunteers North Carolina’s way.

“We are excited and motivated to help out our neighbors to the north,” said S.C. Republican Party Chairman Chad Connelly at an N.C. appearance last month with Republican National Committee Chairman Reince Priebus.

Follow Mary on Twitter @mcurtisnc3