I'll preface this by saying I haven't heard much about this race.
Maybe it was Asa Hutchison running a good campaign, but I was kind of shocked I heard less about this race. Ross had bullied his way into the Dem primary with his fundraising, caused Bill Halter to end his bid, and it was supposed to be neck and neck between Hutchison and Ross. Ross had several potential advantages - being a fairly conservative Democrat, was a very Arkansas kind of a guy, and had Bill Clinton on his behalf. What went wrong for him or right for Hutchison?
Clinton's influence in Arkansas has been waning for some time now.
Even earlier, despite his own popularity, Clinton was unable to generate coattails for fellow AR Democrats for several occasions (most evidently in 1996).