(CNN) - Though he had publicly suggested Mitt Romney pick Sen. Marco Rubio to join the GOP ticket, former New York City Mayor Rudy Giuliani said Wednesday in an interview on CNN's "Piers Morgan Tonight" that he is "very happy with the choice of Paul Ryan" – although the pick was a "gamble."
"I think that Governor Romney has made a gamble here. He's taken a risk," Giuliani said.
Earlier in the day, Giuliani slammed Vice President Joe Biden for being "not very smart" in response to controversial comments the vice president made at a campaign stop Tuesday.
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