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"He just doesn't have any experience. All he has is experience of being a legislator," Christie said on "Good Morning America" today. “We've tried that as a party and as a country and it doesn't work."
Christie's argument centers around Rubio’s age – 44 – and his belief that Rubio is not a strong enough candidate to take on Hillary Clinton in the general election if she wins the Democratic nomination.
"We need to make sure we nominate someone who not only can beat Hillary Clinton but also can manage the government and get it back on the right track once they're elected president of the United States," Christie, 53, argued. "No need to take those chances on someone who's never managed anything larger than a 30-person Senate staff."
In a UMass Lowell poll released today, Rubio is polling at 15 percentage points (steadily rising to second place) while Christie is stuck at 5 percentage points in New Hampshire.
But Christie pointed out today that the polls showed Trump winning the Iowa caucuses before his second-place finish.
On the controversy over the Iowa caucuses, and the accusations from Ben Carson and Donald Trump that Ted Cruz “stole” the election there, Christie said the election is over and that the candidates should move on.
"I don't think any time in politics when you lose and you ask for a do-over that's something that gives people a lot of confidence in your leadership,” Christie said. "The results are the results. You move on to the next contest and try to win the next contest; stop focusing on the rearview mirror.”
Christie said that even if he doesn't beat Rubio Tuesday, it's not the end of his campaign.
"No,” he said, “it's not a concession to that at all.”