Newswise — The overriding question as voters in 24 states go to the polls on Super Tuesday?

"Has Barack Obama's movement grown strong enough that he can win in states where he hasn't campaigned extensively?" asks Larry Butler, chair of the political science department at Rowan University.

"To this point Obama has only been able to win in areas where he's had the time and money to rally the troops on the ground," says Butler, author of the book Claiming the Mantle: How Presidential Nominations Are Won and Lost Before the Votes Are Cast.

"He's doing very well where he can be on the ground, keeping people excited."

But because of the number of states in the Feb. 5 Super Tuesday primaries, it's unclear how Obama will fare in states where he hasn't been able to rally voters, according to Butler. That's where a campaign's organization is key, he notes.

Frontrunner Hillary Rodham Clinton has more endorsements and many of hers are "Superdelegates." Furthermore, Clinton's presidential campaign is more sound organizationally than Obama's, says Butler.

"They both have money but Clinton has an organization that has been there for her family since 1992. They've been nurturing it for 15 years. It's broad-based and it's grassroots.

"Obama has a movement. But Hillary Clinton has a campaign. A good campaign always beats a movement."

While Rudy Giuliani's decision to drop out of the GOP race earlier this week clearly bolsters John McCain's White House bid, the effect of the withdrawal of John Edwards from the Democratic race is less clear-cut, says Butler.

"I just don't know where his people go," says Butler. "The fact that he's been able to pull 10-15 percent despite doing poorly in early states tells me that there is no obvious second choice for his supporters.

"I think this is it for Edwards in his presidential bids, but, by bowing out now, it helps him maintain his stature for his future in politics, perhaps in a cabinet position."

Meanwhile, McCain, whose Republican campaign was in tatters last summer, has a chance to come out of Super Tuesday as the GOP nominee. Still, says Butler, he'll have to work hard to build support, particularly among conservatives.

Butler notes that McCain has asked to speak at the Conservative Political Action Committee Conference shortly after Super Tuesday, an event he has skipped in the past.

"At that point, he's likely to be the presumptive nominee," says Butler. "He understands he has some work to do to unify the base behind him."