Sen. Richard Lugar, R-Ind., one of the longest-serving members of the Senate, lost the Republican primary to state Treasurer Richard Mourdock on Tuesday. With 14 percent of the vote counted according to the AP tally, NBC News has called the race for Mourdock, who leads Lugar 61 percent to 39 percent.
Facing a headwind of tea party anger and hamstrung by a lingering story about his out-of-state residency, Lugar's campaign struggled badly in the final weeks of the campaign to make a forceful case for his re-election. Mourdock's bid was boosted by national conservative support from groups like the anti-tax Club For Growth, which ran a series of negative ads against the incumbent.
Mourdock advances to a general election showdown against Rep. Joe Donnelly, who was unopposed in the Democratic race.
Lugar, who was first elected in 1976 and serves as the ranking Republican on the Senate Foreign Relations Committee, is the first incumbent senator to be defeated this year.