(Paul Sancya/AP Photo)

Newt Gingrich nearly swept South Carolina on Saturday, winning all but one of the state's bellwether counties and collecting votes from every region.

Mitt Romney's bright spot came in Charleston, the city on South Carolina's coast that's home to moderate GOP voters who handed John McCain his largest county victory in 2008. Romney edged Gingrich 36 percent to 33 percent in Charleston on Saturday night. Romney also won the neighboring coastal county of Beaufort.

Romney also managed to take Richland, a large county in the Columbia area in the center of the state that also supported McCain in 2008.

Gingrich won every other county, going 43 of 46.

Exit polls and the final results map showed Gingrich winning both social-conservative votes that went to Mike Huckabee in 2008, enough coastal moderate votes that went to McCain, and most of the McCain-backing center of the state.

The former House speaker dominated in the socially conservative northwest portion of South Carolina, Huckabee's stronghold in 2008.

Despite Rick Santorum's continued play for the socially conservative, family-values vote, exit polls showed Gingrich dominating statewide among "very conservative" voters, tea-party supporters, voters who say abortion should be illegal in all cases, and white evangelical or born-again Christians. Gingrich took Greenville, South Carolina's northwestern bellwether county, 40 percent to Romney's 25 percent and Santorum's 18 percent.

The former speaker won in coastal Horry County, where moderate voters could have given Romney a boost, with 46 percent to Romney's 30 percent. Exit polls showed Gingrich trailing Romney among self-declared moderates 31 percent to 36 percent statewide.

The middle of the state, which supported McCain in 2008,  figured to be a battleground - and Gingrich dominated there, too. While Romney took Richland, Gingrich took Lexington, the other large county in the Columbia area, with 37 percent to Romney's 31 percent. Gingrich won seven of the eight central counties that all supported McCain in 2008, counting the two mentioned above.