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LAKEWOOD, CO - AUGUST 14: Republican vice presidential candidate U.S. Rep. Paul Ryan (R-WI) Ryan shakes hands with supporters after a rally at Lakewood High School August 14, 2012 in Lakewood, Colorado.
The vice presidential candidates often are able to say things that the presidential candidates can't... or won't. They can be the attack dogs of the campaign or perhaps the ids to their running mates' super egos.
Madeleine talks to vice presidential scholar Joel Goldstein a law professor at Saint Louis University