Christie: Romney's success isn't shameful

New Jersey Gov. Chris Christie called again for Mitt Romney, his preferred candidate in the Republican race for president, to release his tax returns, saying on "CBS This Morning" Thursday that the former Massachusetts governor shouldn't be "ashamed" of his success.

Christie, who backed Romney after weeks of speculation that he would jump into the race, also clarified comments he made about President Obama, who he considers to be an "excellent politician" but an "awful president," in an interview with Erica Hill and Charlie Rose.

Christie wants Romney to release his past tax returns so the race can focus again on Republican issues.

"If Governor Romney were to ask me my advice, I'd say, 'Just get this stuff out there,'" said Christie. "Let people see what it is. I can't imagine there's anything that's all that problematic."

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Christie disputed the focus of a New York Times article published Thursday that characterized as a political problem the wealth Romney earned while running the private investment firm Bain Capital.

"I don't think there's anything to be ashamed of, that he's been a very successful guy in the private sector and made money, built businesses," said Christie. "Staples, Sports Authority, these are all places that were built because of Mitt Romney's ingenuity and his investment and his firm's investment in those companies, so I don't think there's anything to be ashamed of."

One thing Christie isn't ashamed of is publicly complimenting Mr. Obama's political skills and calling him an "excellent politician." Christie clarified that he wasn't praising the president's record.

"I think he's been an awful president," said Christie. "The governing thing is the problem for the president. The politics is what he's best at."

Christie also doubted again that Romney would ask him to run as his vice president if he wins the Republican nomination.

(Watch at left)

"I can't imagine Romney doing it," Christie told Rose. "Now, I have said that I think it's rude to say no to a job that you haven't been offered yet, but if you're a betting man, Charlie, which I suspect you are, I would bet on me being the governor of New Jersey after November of 2012."

At top, watch the full interview with Gov. Chris Christie.