Paul Ryan

Mitt Romney has announced that Wisconsin Rep. Paul Ryan will be his vice-presidential running mate.

"I am proud to announce @PaulRyanVP as my VP. Stand with us today. http://mi.tt/Romney-Ryan #RomneyRyan2012," Romney tweeted on Saturday. 

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"There are a lot of people in the other party who might disagree with Paul Ryan," Romney said Saturday in Norfolk, Va., according to The New York Times. "I don't know of anyone who doesn't respect his character and judgment."

Upon accepting, Ryan said, "The commitment Mitt Romney and I make to you is this," Mr. Ryan said, smiling broadly during much of his address. "We won't duck the tough issues; we will lead. We won't blame others; we will take responsibility. And we won't replace our founding principles; we will reapply them."

Ryan, 42, grew up in Janesville, Wisc. He was elected to the House of Representatives in 1998.