HELENA — Sen. John Walsh said Thursday he is pulling out of the Senate race because his campaign was distracted by the controversy over allegations that he plagiarized a U.S. Army War College research paper. Walsh, a Democrat, said he decided to drop out of the race. He had canceled campaign events this week as he and his family discussed what he would do. The New York Times reported July 23 that Walsh had plagiarized large portions of the research paper in 2007. Walsh will serve out the rest of his Senate term, which ends in early January 2015. “I...