DeWITT, Mich. - Mitt Romney today declined to comment on Jonathan Karl's report that Florida Sen. Marco Rubio is not being vetted as a potential running mate, saying that only he and adviser Beth Myers truly knows who is being considered.

"I get a kick out of some the speculation that goes on," said Romney in an interview with Fox News' Sean Hannity.

"I'm not going to comment on the process of course but I can tell you this, only Beth Myers and I know who is being vetted," said Romney.

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