Christie and former Florida Governor Jeb Bush, who are vying with Rubio for support from establishment Republicans in Tuesday’s New Hampshire nominating contest, 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.

But Christie accused Rubio of resorting to “a memorized 30-second speech.”

“We tried it the old way,” Bush said of electing Obama, saying the country got “soaring eloquence” but few results.

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

Rubio said the legislation was never going to pass without popular support, and that 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.

Billionaire real estate tycoon Donald Trump holds a solid lead in polls in New Hampshire, with Rubio rising quickly into second place after a surprisingly strong third-place showing, behind U.S. Senator Ted Cruz and Trump, in Monday’s first nominating contest in Iowa.

The debate comes just three days before New Hampshire goes to the polls in the state-by-state battle to pick the candidates for the Nov. 8 presidential election.

Cruz bypassed an early chance to tussle with Trump, refusing to repeat his criticism from earlier this week that he did not have the temperament for the White House.

Trump noted that Cruz did not want to take him on.

“He didn’t answer your question, and that’s what’s going to happen with our enemies and the people we compete against,” Trump said. “We’re going to win with Trump and people back down with Trump, and that’s what I like.”

Trump and Rubio have become the favored targets of the other Republican candidates this week as the candidates launched an all-out offensive across New Hampshire.

A Suffolk University/Boston Globe poll on Friday found Trump leading with 29 percent, followed by Rubio and Ohio Governor John Kasich.

Not on stage was businesswoman Carly Fiorina, who failed to meet host ABC’s qualification debate requirements. Fiorina released an open letter excoriating the debate process as “broken.”