Soon, he made a big mistake -- telling Clinton she's "been in a position to help" solve problems for 30 years. "The problem is, you talk, but you don't get anything done, Hillary. You don't," he said.
That teed up Clinton for a memorable answer.
"You know, back in the 1970s, I worked for the Children's Defense Fund, and I was taking on discrimination against African-American kids in schools. He was getting sued by the Justice Department for racial discrimination in his apartment buildings," she said.
"In the 1980s, I was working to reform the schools in Arkansas. He was borrowing $14 million from his father to start his businesses. In the 1990s, I went to Beijing and I said women's rights are human rights. He insulted a former Miss Universe, Alicia Machado, called her an eating machine," Clinton said. "And on the day when I was in the Situation Room, monitoring the raid that brought Osama bin Laden to justice, he was hosting the 'Celebrity Apprentice.'