The son of Colorado Sen. Mark Udall was arrested Wednesday on suspicion of breaking into cars and possessing heroin, according to a local news report.According to authorities cited by the Boulder, Colo., newspaper The Daily Camera, 26-year-old Jed Udall allegedly broke into three cars. He was found with heroin in his pocket, a local sheriff told the paper. He was booked into jail and later released.Mark Udall, a Democrat, is up for reelection this year. Republicans hope to find a competitive challenger among the several entrants in the primary field, but, so far, Udall appears to be in a strong...