Rubio comes under heavy fire

Rising Republican contender Marco Rubio came under heavy attack in a presidential debate on Saturday from rivals who accused him of being too inexperienced for the White House and walking away from an immigration reform plan he championed.

In a fiery debate three days ahead of Tuesday’s New Hampshire primary, billionaire real estate mogul Donald Trump also battled with rival Jeb Bush over the use of eminent domain to seize private property and called for a compassionate approach to those who might lose their health insurance if Republicans repealed Obamacare.

Polls show Trump leading in New Hampshire, the second of the state-by-state nominating contests to select candidates in the Nov 8 election, with Rubio coming fast after a surprisingly strong third-place finish on Monday in Iowa, behind US Senator Ted Cruz and Trump.

The heavy attention commanded by Rubio reflected the changing dynamics of the Republican race, as the US senator from Florida attempts to become the party establishment’s choice to challenge the controversial Trump and conservative Cruz.

New Jersey Governor Chris Christie and former Florida Governor Jeb Bush, who are vying with Rubio for support from establishment Republicans in New Hampshire, compared Rubio’s experience in the Senate to that of President Barack Obama, who also was a first-term senator when he was elected.

"He simply does not have the experience to be president of the United States and make these decisions," Christie said of Rubio.

"We’ve watched it happen, everybody, for the last seven years.

The people of New Hampshire are smart, do not make the same mistake again."

Rubio said he had shown in the Senate that he could get things done, and questioned Christie’s record.

"I think the experience is not just what you did but how it worked out.

Under Chris Christie’s governorship of New Jersey, they’ve been downgraded nine times in their credit rating," he said.

Christie accused Rubio of resorting to "a memorised 30-second speech."

Bush noted that by electing Obama, the country got "soaring eloquence" but few results.

Christie also led the charge against Rubio on immigration, criticising him for backing a comprehensive reform bill in the Senate but then abandoning it when it foundered in the House under heavy conservative opposition.

Rubio said the legislation was never going to pass without popular support, and the United States needed to begin enforcing immigration laws and improve border security before the public would have the confidence to back it.

"The question is did he fight for his legislation. It’s abundantly clear that he didn’t," Christie said.

Bush attacked Trump for using eminent domain, which allows governments to seize private lands for projects for the public good, to help him build casino complexes in Atlantic City.