"No matter how good your resume is, there has to be a lot of growing as chief executive. And I think that's the key," said former Gov. Jim Edgar, a distinguished fellow with the University of Illinois' Institute of Government and Public Affairs. "I look back to the most successful president in the history, Abraham Lincoln, who had probably a weaker resume than Barack Obama, and he was able to do remarkable things as president."

Edgar and Obama overlapped at the Illinois statehouse for two years. Edgar was governor 1991-99 and Obama was a state senator 1997-2004.

Edgar said in a university-issued news release he thought Obama's grace period would be short, given the deep economic crisis and wars he will face immediately. He urged Americans to be as patient as they can.

"There's going to be a lot of pressure to just move quickly to the left and maybe not worry about people in the center or people on the right," Edgar said. "But as president he's got to govern from the center and bring both sides of the spectrum with him."