That's what the primaries are for. Lindsey beat Buddy Witherspoon in the primary of '08, and that was that. He was the official nominee.
Party officers can't openly endorse some other candidate without resigning their office. Individual members can do what they like, iirc.
Since getting into the Senate, Graham has drawn a lot of support from the Democrats. They actually refuse to run against him. The only reason that he had a Democrat challenger in '08 was because a conservative filed for and got the Democratic nomination.
What just happened to Inglis in the Fourth Congressional District needs to happen to Graham as well. 2008 just wasn't the time.
I’m seeing similarities with Graham and the problem we have/had in Florida with Crist. Crist has been able to win elections only with of Democrat support. Once the GOP removed its support, Crist banked on Dem and Ind. voters to put him into the Senate.
For the good of the country, I hope there is another Republican in SC who can take Graham out; or at least pose such a threat he is forced to switch parties.