Rubio is up 10 points in less than a month in the poll conducted before the New Hampshire primary.
Two two met for breakfast at Sylvia's in Harlem.
We need a strong leader with experience, ideas and resolve," the former president says.
The New York Daily News and the Union Leader have attacked Trump regularly.
"He’s not as conservative as me, and his record is not nearly as good as mine.”
"I can give you five lines they say every single day,” he said of opponents.
Trump said he might have to take “a little bit tougher stance” on Kasich.
“I think it’s a sad situation," the Ohio governor said.
Trump did not directly answer a question about an endorsement.
Amie Parnes 02/10/16 06:00 AM EST
Allies say her campaign’s problems boil down to a fundamental problem: messaging.