Democratic Presidential candidates Barack Obama and Hillary Clinton are now focusing on the next primaries in North Carolina and Indiana.

North Carolina is offering the biggest prize of the two, with 115 delegates at stake, and about 75,000 people in the state have already cast their ballots in a new system that allows residents to register and vote the same day.

Obama is heavily favored to win in North Carolina, but it is not just whether he wins, it's who he wins.

It was in North Carolina that Obama brushed off Clinton's attacks.

"You just gotta kind of (dusts off his shoulder and gets standing applause) ...you know..." said Senator Barack Obama.

And it could be just the place to brush aside her Pennslyvania victory.

A Los Angeles Times poll, taken before the Pennsylvania primary, shows Obama ahead by 13 points with 17 percent undecided.

Not surprising since the state's demographics favor him.

The research triangle is filled with affluent and well educated liberals and in the last presidential election -- one in four voters were African-American.

Obama wins handily with both groups.

The big unknown is the 30 percent of voters here who are low income whites.

It's a group Clinton suggests Obama can't win in a general election.

She's courting them aggressively here.

"If we don't begin to pay attention to the growing inequality in wealth and the loss of good jobs that supported families, we won't recognize our country,” said Senator Hillary Clinton.

So North Carolina will be an important test

“If Obama can in fact appeal to the undecided white males there, that are largely going to be from rural and suburban areas, I think that would be a huge victory for him,” said Jennifer Palmer, Vice President for the Center for American Progress.

On the other hand, if Clinton wins affluent whites or African-Americans.

“I think that would show that his base was slipping and that people may be becoming anxious about his candidacy,” said Palmer.

North Carolina and Indiana hold their primaries on May 6th.

Indiana has 72 delegates up for grabs.