Rubio: I don't want VP job and won't be asked

(CBS News) Florida Senator Marco Rubio went to his greatest lengths yet to insist that he isn't interested in being Mitt Romney's vice president, insisting in a Thursday interview that he not only didn't want the job, but didn't expect to be asked.

Rubio responded with an unequivocal "yes" when asked by National Journal's Major Garrett if he would turn down a request from Romney to serve as Vice President. "But," Rubio added, "you know he's not going to ask." Rubio was speaking at NJ's "Next America" forum.

The senator is often listed as one of the top-tier VP candidates for his conservative views, good relationship with the Tea Party and possible ability to attract minorities to the GOP ticket. He has always protested the inclusion of his name on the potential list, saying he doesn't think he'll be asked to fill the position and that it's not his intent to leave his current job.

Rubio endorsed Romney on March 28, saying, "It's increasingly clear that Mitt Romney's going to be the Republican nominee," and urging the country to "come together behind who I think has earned this nomination and that's Mitt Romney."

Check out CBS News political director John Dickerson's "Hotsheet Live" Reporters Roundtable on Romney's VP pick in video to left.

The endorsement only fueled speculation that Rubio might not be as loathe to take the job as he suggested. But he went so far as to propose a fellow candidate in the Republican veepstakes for the job: Ohio Sen. Rob Portman.

"We've got a lot of really talented people out there that Mitt Romney can get to pick from. And I think a lot, Senator Rob Portman would be a phenomenal choice for vice president, that's where I would encourage him to look because I'm enjoying my service in the Senate," Rubio told Garrett.

But a verbal slip in which Rubio referred to his career after serving as vice president will probably only continue speculation about his future.

"Three, four, five, six, seven years from now, if I do a good job as vice president -" Rubio said, before catching himself. "Did you all get that?" Garrett crowed to the audience.

Rubio quickly corrected: "If I do a good job as a senator instead of a vice president, I'll have a chance to do all sorts of things, including commissioner of the NFL which is where the real power is!"