I believe that the fact that there were so many challengers running scared the national organizations away from picking one to back. I presume they held their gunpowder to see if any got to a run-off. Not Bright's fault at all imho.
This was exacerbated by Bright’s financial problems which involved an underwater trucking business ...
Bright addressed these issues and didn't shy away from it. He was elected to the State Senate with these financial problems as a part of his history.
Bright came into the race with only two other challengers at the time. Failed congressional candidate, Richard Cash, and the heir apparent-Nancy Mace, who performed badly in interviews.