South Carolina also has a state guard: http://www.sg.sc.gov/.
The history page has some interesting information:
To rectify this situation the National Defense Act of 3 June 1916 was amended on 21 October 1940 to allow the establishment of state defense forces. In South Carolina the enabling act was the Act Establishing the South Carolina Defense Force, signed into law by Governor Burnet R. Maybank on 21 March 1941.The South Carolina Defense Force (SCDF) was organized into a Headquarters, four regiments of three battalions each, and at least one independent battalion. Initially those wishing to enlist or be commissioned had to be between the ages of 21 and 55, in good health, and of good character. The minimum age quickly fell to 17 and there are indications that a few men served at an even younger age. The uniform was to be Confederate Gray.