They fear empty seats would present a devastating image to President Barack Obama's campaign, The Hill reported.
Jen Psaki, the traveling Obama press secretary, said she was confident all 73,778 seats at Bank of America Stadium -- the home of the NFL Carolina Panthers -- will be filled when Obama gives his acceptance speech Thursday.
"We have a great ground operation in North Carolina and we've registered more voters than any other state," she said. "Our goal is to leave North Carolina better than we came in."
Obama delivered his 2008 acceptance speech to a packed house at Mile High Stadium in Denver. A former administration official told the Times "this isn't 2008 and this isn't Colorado."
"And I think the fear is that the campaign aimed too high on this one," the former official, whose name was not reported, told the newspaper. "After all, this is a southern state, which leans red and only helped Obama win in 2008 by very slim margins.
Tickets for the acceptance speech were still available a few days ago.
The Obama campaign is giving one ticket to the speech to volunteers who work 9 hours over three shifts.
Republicans don't doubt Democrats can fill the stadium, but say the effort will be have to be contrived to succeed.
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