CNN reports:

“They will have more than 85,000 people, perhaps more than 90,000 people, in this stadium by the time Barack Obama speaks,” Chief National Correspondent John King said Thursday evening. “There is a concern that the Obama campaign may have issued as many as 20,000 more tickets for this event” than the stadium can hold.

Local authorities say they are working with the Secret Service to get as many people into the stadium as possible. But there is a concern that several thousand people could be turned away.