(Image Credit: ABC News)

Mitt Romney, the presumptive Republican presidential nominee, currently faces a dynamic similar to the one President Bill Clinton faced during his first presidential run 20 years ago: a long, bruising primary, driving up his unfavorable ratings. Clinton turned it around. Can Romney?

"I doubt it," the former president said.

"Mr. Romney has a different challenge than I did," Clinton said. "Even though he had a bruising primary and higher negatives and I did too. Mine was just one long character attack. It was a personal attack on me. You know, 'You shouldn't have this guy be president.'"

Clinton was able to turn it around, he said, because "the American people are inherently fair. I named Al Gore. We reintroduced our economic plan. Then we reintroduced ourselves to the American people. But we never had to change what we were saying from primary to the general. The problem that Governor Romney has, is his character attack was 'You don't really know what he believes. He did this, he says that.'

"He started this campaign in the aftermath of that tea party victory in 2010," Clinton said, "when all the people on the far right of the Republican party actually believed a majority of the voters had embraced the specific things they were saying. So it created a horrible dilemma for Romney. And the poor man who got in trouble for the Etch-a-Sketch remark. That's like the saying, 'There is nothing more damaging in politics than telling the truth.' I mean, the truth is, that's what he's gotta do."

The former president was referring to a comment by Romney adviser Eric Fehrnstrom, who - when asked by CNN if Romney had run too far to the right to win the primaries - said, "I think you hit a reset button for the fall campaign. Everything changes. It's almost like an Etch-A-Sketch. You can kind of shake it up and restart all of over again."

Clinton said Romney has to "convince the swing voters that he'll be moderate enough and open enough and inclusive enough to be an effective president, and effective on the economy. And hope that the Republican base voters say, 'Well, okay, so he maybe wasn't as right-wing as he claimed to be in the primary. Still more conservative than President Obama. I guess I'll vote for him anyway and I won't stay home.' That's a much harder job. So I doubt if he can do it. But it's going to be interesting to watch."

The former president made his comments in an exclusive interview for "Good Morning America" focused on the work of Clinton Global Initiative University.

-Jake Tapper