“I am curious of the demographics of the two counties in SC Romney won.”
The two counties in South Carolina that Romney won are Charleston and Beaufort, which consists largely of Charleston suburbs. Romney ran close to Gingrich in Berkeley and Dorchester Counties as well. These also border on Charleston. Gingrich swept the inland part of the state.
I stand corrected. Romney won a third county. That is Richland County, which contains the state Capitol of Columbia, and he ran close in the Columbia suburbs of Lexington County. I see a pattern, where Romney has no appeal to Republican voters outside urban and suburban areas.