SC feels a lot like TX-2018 where people wouldn't believe that it was close until they saw it with their own eyes. Even though now it doesn't seem that farfetched, polling indicates its close, and Graham's behavior seems to confirm that.
Meanwhile, with the insane amount of $ that Gideon and Harrison have raised, do we think that they're also just doing better because they've been flooding the airwaves too?
I don't know about SC being similar to TX in 2018. While Graham does seem to be widely reviled, and an especially good target because he animates the left and the right is largely apathetic about him, I can't get over the racial politics of South Carolina.
I just do not see how Harrison is able to assemble a coalition that gets him 48% of the vote in SC. I think the only spoiler/outside chance is if the Constitution party nominee somehow eats up a sizable share of the vote -- 5-10%, leaving Harrison an outside shot with mid-40% at winning.