As it was, South Carolina would (in the past) have a Senator from the Up Country and Low Country (Thurmond being from the "Up" and Hollings from "Low" -- although there was a 12-year overlap when Olin Johnston and his interim successor, Donald Russell, along with Thurmond represented the Up Country -- Thurmond's elected predecessor, Burnet Maybank was a "Low Country" Senator), so Ravenel could argue that his being Senator would more fairly geographically represent the state (as DeMint, too, is an Up Country Senator).
The geographic-balance issue would certainly help Ravenel or Sanford. While each election is an independent event, it could certainly add a few points to a candidate if he can claim that his region is being ignored.