PHILADELPHIA -- Bill Clinton isn't used to being the second act, but he slipped comfortably into that role Tuesday night when making a forceful case that his wife is the proven change-maker who should become president of the United States in November.
After struggling to control his temper and his outbursts on the campaign trail in 2008, the former president has been a far more disciplined, supportive spouse on the campaign trail this time -- traveling across the country to campaign for his wife and carefully avoiding GOP nominee Donald Trump's provocations.
On Tuesday night, he delved deeply into her biography to cast her as change agent -- hinting that while she might not be as natural a politician, she has spent her life fighting to improve people's lives, particularly the lives of children and the disabled.
"She's the best darn change-maker I've ever met in my entire life. This is a really important point," Clinton said of his wife. "This woman has never been satisfied with the status quo ... She always wants to move the ball forward. That is just who she is."
At a time when many voters say they don't trust Hillary Clinton, her husband sought to soften her harder edges. He recalled how relentlessly he had pursued her, proposing to her three times before she accepted.
Bill Clinton brought to the convention floor a certain rock star status within the Democratic Party. He has shown his unique ability to fire up the base and turn out voters.
He holds a much higher favorability rating than his wife. Among Democratic voters, 79% view him favorably.
The former president has turned into a frequent target for Trump, who has railed about the former president's personal life from the campaign trail.
"She's married to a man who is the worst abuser of women in the history of politics. She's married to a man who hurt many women," Trump said at a rally in Spokane, Washington. "And Hillary was an enabler and she treated these women horribly. Just remember this. And some of those women were destroyed not by him, but by the way Hillary Clinton treated them after everything went down."
Trump has also seized on Clinton-era policies, going after NAFTA, which Trump has vowed to renegotiate.
"She doesn't understand trade," Trump said. "Her husband signed perhaps in the history of the world the single worst trade deal ever done."
Bill Clinton has also faced scrutiny over his legislative record directly from voters on the campaign trail. In April he was confronted at a campaign event for his wife in Philadelphia by Black Lives Matter activists over his administration's 1994 crime bill.
"You are defending the people who killed the lives you say matter," Clinton pushed back from the podium.
On the campaign trail, Hillary Clinton has at times tried to distance herself from her husband, repeating regularly that she is running on her own record, not "running for her husband's third term."
But she has had to clean up after him at times -- most recently in the aftermath of Bill Clinton's private, impromptu meeting with Attorney General Loretta Lynch at the Phoenix airport in June. The meeting was widely criticized given that the attorney general was overseeing the investigation into Hillary Clinton's use of a private email server while secretary of state.
"I think, you know, hindsight is 20/20," Hillary Clinton said of the meeting in an interview with NBC News. "Both the attorney general and my husband have said they wouldn't do it again, even though it was from all accounts that I have heard and seen, an exchange of pleasantries. But obviously no one wants to see any untoward conclusions drawn, and they've said, you know, they would not do it again."
Still, Hillary Clinton sees her husband as an asset.
She has pledged to give him a role in a potential second Clinton administration dealing with the economy, trying to capitalize on her husband's economic record while he was in the White House.
"I'm going to put (him) in charge of revitalizing the economy," Clinton said in Fort Mitchell, Kentucky, this May. "You know he knows how to do it, especially in places like coal country and inner cities and other parts of our country that have really been left out."
Bill Clinton would still be entering unchartered waters should the White House be helmed by his wife, becoming the first man to fill the role of president's spouse.
Hillary Clinton has suggested that in lieu of first lady he could be called "first dude, the first mate, the first gentlemen."
Bill Clinton has suggested "first laddie."
"I don't know, I don't really know because it'd be such a precedent," he said of a potential title. "I don't care what I'm called, it's more about what I'm called to do."