Actually, South Carolina was suprisingly bright for the Democrats, all things considered. Bush showed less improvement here than he did nationally compared to 2000. The Dems picked up a seat each in the State House and the State Senate. The Senate race was DeMint's to win and he did, but the GOP and its allies had to spend a lot more time and effort than they had hoped to. SC is a long way from being a swing state, but I think the Dems can hope to pick up a constitutional office or two in '06. Lt, Gov. and Sec of Agriculture are probably the likeliest targets and I think that the Dems will be able to keep the Superintendency, even if Inez decides to not run for re-election.
Your assertions about Democratic gains in the SC state legislature are not true. Republicans gained 1 state house and 2 state senate seats.
http://www.ncsl.org/ncsldb/elect98/profile.cfm?yearsel=2004&statesel=SC