Bill Clinton hit the campaign trail for his wife's presidential bid on Monday, telling voters in New Hampshire that “nobody is better qualified” than Hillary Clinton -- as his presence stoked revived criticism from Republicans about his personal and professional past. 

Front-running Republican candidate Donald Trump has led the attacks, asking how Hillary Clinton can position herself as a champion for women while bringing her husband to campaign events despite his adulterous past. 

“I hope Bill Clinton starts talking about women's issues so that voters can see what a hypocrite he is and how Hillary abused those women,” Trump tweeted Saturday.

He also recently suggested that Clinton was not an “innocent victim” in her husband’s extra-marital activities.

“She would go along with him,” Trump told Fox News.

The comments follow similar ones since Clinton, the Democratic front-runner, announced a few weeks ago that she was going to deploy her “not-so-secret weapon” Bill Clinton in January. But the Clinton campaign has hit back, accusing Trump of having a "penchant for sexism." 

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Hillary Clinton is in a far better position this primary season than she was the last time Bill Clinton stumped for her -- in the 2008 primary against Barack Obama. Clinton has 54 percent of the national primary vote and leads her closest challenger, Vermont Sen. Bernie Sanders, by 23 percentage points, according to a RealClearPolitics poll average.

However, she needs a boost in early-voting New Hampshire where Sanders trails by less than 5 points, with Election Day on Feb. 9.

On Monday, Clinton began his speech at Nashua (N.H.) Community College by calling himself a “happy grandfather,” then argued that his wife’s platform represents voters’ best chance at making America safer and restoring widespread economic prosperity.

“I think it’s the best plan to have the most rapid movement toward broadly shared prosperity,” he said.

Clinton closed his roughly 25-minute speech by saying he and his wife “fell in love 45 years ago” and that “everybody goes to the White House with the best intentions.”

He also made a stop Monday in Exeter, N.H., while Hillary Clinton was in Iowa, which votes first, on Feb. 1.

Hillary Clinton said upon announcing that her husband would join her on the trail:  “We’re going to cover as much ground in New Hampshire as we possibly can, see as many people, thank everyone who’s going to turn out and vote for me to try to get some more to join them.”

The former president has already been on the 2016 trail for his wife, appearing on stage with pop star Katy Perry in late October before a key fundraising dinner in Iowa. However, his appearances starting Monday are his first stump speeches.

Clinton until now has largely remained behind the scenes, raising money and offering campaign advice to the former New York senator and secretary of state.

Though polls show he is still one of the most popular political figures in American politics, his efforts during Hillary Clinton’s failed 2008 White House bid were occasionally criticized -- including his suggestion that race was a factor in eventual-winner Obama defeating his wife in the South Carolina primary.

“Does anybody remember when Bill Clinton, in 2008, worked long and hard for Hillary? She LOST! Now Bill is at it again. Just watch,” Trump tweeted this weekend. 

The Republican National Committee also used Clinton's appearance Monday to question his paid speaking gigs while his wife was secretary of state. A spokesman said his presence only "reinforces the fact the Clintons are untrustworthy and have used public service to enrich themselves and reward their friends." 

Sanders told ABC News on Sunday that he didn’t object to Clinton joining the campaign trail.

“We have enormous problems facing this country, and I think we got more things to worry about than Bill Clinton's sexual life,” he said. “Maybe Donald Trump might want to focus attention on climate change. … Maybe Donald Trump should understand that we should raise the minimum wage. … Maybe he should focus on those things.”

Trump spokeswoman Katrina Pierson recently suggested that the campaign will make an issue of Bill Clinton’s past behavior if his wife continues with the accusations of sexism toward Trump, while Democrats continue their broader attack on Republicans about their so-called “war on women.”

“Hillary Clinton has some nerve to talk about the war on women and the bigotry toward women when she has a serious problem in her husband,” she told CNN.