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Mitt Romney's sons describe their dad's 'corny jokes' on the campaign trail

Rock Center

From using the word "guffawing" to talking about the perfect height of Michigan's trees, Mitt Romney's sons said the presidential contender's campaign trail jokes are part of his goofy personality.

"He's just dad. He's just, he's a little goofy and that's just, you know, part of his charm I think," said Tagg Romney in an interview with NBC's Peter Alexander airing Thursday, July 19 at 10pm/9c on NBC's Rock Center with Brian Williams.

Craig Romney admits that sometimes his dad's joke work and sometimes they don't.

"It's the same corny jokes we grew up with. I mean, we're used to it. It's just kind of part of his personality, but he's always trying to entertain and sometimes it's successful and sometimes it's not,' Craig Romney said.

Editor's Note: NBC Correspondent Peter Alexander's interview with Romney's five sons airs Thursday, July 19 at 10pm/9c on NBC's Rock Center with Brian Williams.