
First lady Michelle Obama pleaded with North Carolina voters to keep 'working your hearts out for my girl' – Democratic presidential candidate Hillary Clinton – then declared: 'First ladies, we rock.'

Obama, who broke tradition by deftly wielding the hatchet to take apart Donald Trump on the campaign trail, eased off some of her harshest attacks as she delivered a glowing tribute to Clinton, who was seated behind her during lengthy remarks.

But she declared Hillary Clinton, a one-time bitter rival of her husband, 'my friend,' and cast grave doubts about Donald Trump's fitness for the job of president.

'We want a president who takes this job seriously,' Obama said. 'And has the temperament and maturity to do it well. Someone who is steady. Someone who we can trust with the nuclear codes.'

And she implied that Trump – who was revealed talking about grabbing women by the crotch in an infamous 'p****' tape – was a bad influence on the nation's tots.

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Star power: The joint appearance in Winston-Salem of Michelle Obama and Hillary Clinton is a sign of the Democratic candidate's campaign's desire for her appeal to rub off

First ladies united: Michelle Obama used a rally in North Carolina to offer her warmest endorsement of Clinton yet - appearing alongside her and enthusing a large crowd

She's with her: Clinton drew crowd of thousands at the Lawrence Joel Veterans Memorial Coliseum at Wake Forest University – but it was Michelle Obama who was the real draw

Look at the crowd: Clinton appeared delighted by the scale of turnout at the rally

Enthusiastic response: Michelle Obama and Hillary Clinton's joint appearance was met with warmth from a crowd of supporters

Together: 'I wish I didn't have to say this, right, but indeed dignity and respect for women and girls is also on the ballot in this election,' Clinton said introducing Michelle Obama

'We know the influence our president has on our children,' she said. 'They turn on the TV and they see the most powerful role model in the world – someone who shows them how to treat others. How to deal with disappointment. Whether to tell the truth. They're taking it all in,' she said.

Clinton welcomed the assist from one of the most popular political figures in the country in her effort to portray Donald Trump as unacceptable as she tries to drive up turnout in a state that helped sweep Barack Obama into office.

'Is there anyone more inspiring than Michelle Obama?' Clinton gushed at the start of her remarks before a huge student crowd - far larger than the ones the Democratic candidate is used to.

And, Clinton added, 'I do know something about being first lady of the United States.'

Clinton drew crowd of thousands at the Lawrence Joel Veterans Memorial Coliseum at Wake Forest University – though it's not clear how many came to see the first lady, who uncorked a withering attack on Donald Trump over his treatment of women this month.

The crowd was 11,000, according to the Clinton campaign, a large gathering for a campaign that focuses on deftly-presented smaller events that don't match Donald Trump's large rallies.

The first lady made references to some of Trump's policies and statements, like a wall on the U.S.-Mexico border, but steered clear of policy.

'We want someone who is a unifying force in this country. Someone who sees how differences not as a threat but as a blessing,' she said, as a seated Hillary Clinton nodded repeatedly in approval.

She acknowledged the unprecedented role of her unrestrained campaigning while a sitting first lady, a job with no salary and no official description.

'That may be true. But what's also true is that this is truly an unprecedented election. And that's why I'm out here. I'm out here first and foremost because we have never had a more qualified and prepared candidate for president then our friend Hillary Clinton,' she said.

She spoke about her husband's victory here in 2008, noting that Obama won by about 14,000 votes, a narrow margin in a populous state.

She told the crowd to keep 'working your hearts out for my girl.'

'I wish I didn't have to say this, right, but indeed dignity and respect for women and girls is also on the ballot in this election,' Clinton said introducing Michelle Obama, who sat next to her during Clinton's remarks.

In a signal of the political punch provided by President Obama's wife, it was Clinton who introduced the former first lady.

Clinton ran through her agenda, and pleaded with students and young people in the audience: 'You've got to turn out and vote in this election.'

And she praised her for what she called 'a mean round of carpool karaoke' - a reference to Obama appearing on James Corden's CBS late-night show and singing along to Beyoncé.

The first lady is a potent weapon for Clinton. Her positive approval rating was 59 per cent in a recent Fox News Poll – and hit 95 per cent among Democrats.

'She's been an absolute rock star,' Clinton campaign press secretary Brian Fallon said this week.

Clinton jetted to Winston Salem, in a state that is essential to Donald Trump's narrow path to victory, and where polls have Clinton leading.

Clinton and her team have been warning about 'complacency' among her supporters who might let up on their efforts following widespread reporting after the final presidential debate that challenger Donald Trump is behind.

The first lady has delivered some of the most effective attacks on Trump of any Clinton surrogate, after a series of women came forward to accuse him of groping them or kissing them without permission.

Enthusiastic response: Clinton needs to maximize turn-out in North Carolina among women, African-American and younger voters and deployed the First Lady to that end

Embrace: Michelle Obama has put aside years of frosty relations with Hillary Clinton to campaign for her, first by herself, and on Thursday, with her

Stronger together: Clinton appeared energized by appearing alongside the First Lady, acknowledged as the country's most popular political figure

Let's move the polls: Clinton is hoping the impact of Michelle Obama on the race will be in her favor

'This is not normal. This is not politics as usual,' Obama said last month in New Hampshire. 'This is disgraceful, it is intolerable, and it doesn't matter what party you belong to.'

Trump, who calls himself a counter-puncher, hasn't hit back directly. He did say during the final presidential debate: 'I've gotten to see some of the most vicious commercials I've ever seen of Michelle Obama talking about you, Hillary,' in reference to comments dating to the 2008 primary election.

The White House brushed back and warned Trump that it would be a mistake to hit back.

'I can't think of a bolder way for Donald Trump to lose even more standing than he already has than by engaging the first lady of the United States,' White House spokesman Eric Schultz said this month.

The First Lady's warm endorsement of Clinton is however a departure from their previously chilly personal relations.

During the 2008 presidential campaign, Clinton was offended by Mrs Obama saying: 'If you can't run your own house, you certainly can't run the White House.'

Earlier this year it was said that she wanted Joe Biden to run for the White House.

Clinton referenced Donald Trump's criticism of 'gold star' father Khizr Khan, saying it would ' rub salt in the wounds of military families.'