Senator Barack Obama (D) of Illinois poses alongside Republican Senator Richard Lugar (R) of Indiana at the start of the Senate Foreign Relations Committee business meeting on Capitol Hill in this January 24, 2007 file photo. Richard Lugar, a 35-year veteran of the Senate, was defeated in the Indiana Republican primary by a Tea Party-backed challenger, May 8, 2012, the first Senate incumbent ousted in the 2012 election year.

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