Struggling Republican presidential candidate Jeb Bush brings out the big gun: his mother

(Left) Former US first lady Barbara Bush and her son, Republican presidential hopeful Jeb Bush (right), posing for a photograph with an employee at a diner in Derry, New Hampshire, on Feb 5.
(Left) Former US first lady Barbara Bush and her son, Republican presidential hopeful Jeb Bush (right), posing for a photograph with an employee at a diner in Derry, New Hampshire, on Feb 5.PHOTO: BLOOMBERG

MANCHESTER, N.H./WASHINGTON (Reuters) - Mr Jeb Bush brought out his famous family four days before the crucial United States presidential primary in New Hampshire, tapping his mother on Friday (Feb 5) to scold Republican front-runner Donald Trump over his use of profanity and treatment of women.

In a last-ditch attempt to make a mark on a Republican primary campaign he was supposed to own, Mr Bush lashed out at both Mr Trump and US Senator Marco Rubio, the one-time protege who has eclipsed Mr Bush as the party's establishment candidate in the 2016 White House race.

New opinion polls following Monday's Iowa caucuses showed Mr Trump maintaining a wide lead in New Hampshire's primary next Tuesday with Sen Rubio rising into second place in the state as Republicans battle for the nomination in November's presidential election.

Mr Bush, the former governor of Florida, leaned on his well-known family for support.

While former President George W. Bush appeared in a new ad praising his brother as having "a good heart and a strong backbone", Mr Bush sat with his mother for an interview with CBS show "This Morning".

The two attacked Mr Trump as misogynistic and vulgar after he used a four-letter word in a recent campaign appearance.

"I don't think a president would have ever shouted profanities in a speech in front of thousands of people with kids in the crowd," Mr Bush said. "He does it all the time."

His mother lambasted Mr Trump for criticising Fox News anchor Megyn Kelly after she quizzed him at a Republican debate in August.

Mr Trump made comments widely interpreted as referring to her menstrual cycle. "I don't know how women can vote for someone who said what he said about Megyn Kelly," Mrs Bush said. "It's terrible. And we knew what he meant, too."

Much loved by today's Republicans, the former first lady herself raised eyebrows in 1984 when she reportedly made a derogatory reference to Democratic vice-presidential candidate Geraldine Ferraro, the first woman on a major party ticket, saying: "I can't say it, but it rhymes with rich."

Mr Trump has dismissed Jeb Bush as a "low-energy" loser. The son and brother of US presidents who was expected to glide to the Republican nomination, Mr Bush trails in the single digits in many national polls.

Mrs Bush, who was campaigning for her younger son in New Hampshire, said "America needs" Jeb and drew an implicit contrast to the brash swagger of Mr Trump. "He's got the same values that America seems to have lost. He's almost too polite."

While rivals took aim at him, Mr Trump was forced to miss a rally on Friday in Londonderry, New Hampshire because of a snow storm and was stuck in New York, a spokesman said.

Mr Trump has eschewed much of the one-on-one retail politicking of typical campaigns in favor of large rallies. But in New Hampshire, where voters are used to having candidates' close attention, the strategy could hurt.

Mr Bush seized the opportunity to make fun of Mr Trump on Twitter, pointing out that even his mother was able make it out despite the weather.

"My 90-year-old mother made it out to campaign," he wrote in response to Mr Trump's tweet that he was moving a campaign event to Monday due to a "big storm".

The Bushes chatted with people at a diner in Derry, New Hampshire, according to a pool report sent to news outlets. "Vote for my boy," Barbara Bush told one table. "I haven't seen snow in 1,000 years," she added.

The snow did not stop Ohio Governor John Kasich either. His campaign sent reporters a video of the candidate in a snowball fight after a town hall.

Mr Bush also stepped up attacks on Sen Rubio as lacking in experience and accomplishments, saying on MSNBC the first-term Florida lawmaker had done "nothing" in the US Senate.

He was not the only one piling on Sen Rubio. New Jersey Governor Chris Christie released satirical videos slamming the Floridian as "scripted" for repeating himself in interviews and speeches.

And the New Hampshire Union Leader newspaper's publisher criticised Sen Rubio in an editorial for presenting himself as a Washington outsider, saying Sen Rubio "must think New Hampshire a bunch of rubes".

On the positive side for Sen Rubio, he picked up the endorsement of former Louisiana Governor Bobby Jindal, who dropped out of the Republican race in November.

"I think he's a principled conservative. I think he's the right guy to lead us forward," Mr Jindal said on Fox News.

A Suffolk University/Boston Globe poll released on Friday found that about one-third of likely Republican voters said they could still change their minds.

The poll showed Sen Rubio with 19 per cent, behind Mr Trump's 29 percent. Mr Kasich came in third with 13 per cent, followed by Mr Bush and US Senator Ted Cruz.

For the Democrats, opinion polls show US Senator Bernie Sanders from Vermont with a double-digit lead in New Hampshire over rival Hillary Clinton.

Mrs Clinton went on the attack against Sen Sanders on Thursday in their most contentious debate yet.