Lugar, Mourdock on Republican U.S. Senate Primary

May 4 (Bloomberg) -- Indiana Treasurer Richard Mourdock, Republican candidate for the U.S. Senate, and Senator Richard Lugar talk with Bloomberg's Mark Niquette about their primary race. Polls have shown the race is close heading into the May 8 party primary. Lugar, 80, hasn't faced such a primary challenge since he joined the Senate 35 years ago. (Source: Bloomberg)