COLUMBIA, S.C. — The same forces that aligned for Mitt Romney ahead of his narrow victory in Iowa are working in his favor ahead of South Carolina's presidential primary.

But much can happen before the no-holds-barred contest Jan. 21 in a state that long has picked the eventual Republican nominee.

A splintered conservative base is dividing its support among several of Romney's rivals.

The former venture capitalist's business background seems to be resonating with voters in a state with almost 10 percent unemployment, according to recent public polls, internal campaign polling and interviews with GOP operatives.

A victory Tuesday in New Hampshire would mean that Romney heads into the first Southern contest with momentum from back-to-back successes in the Midwest and Northeast. But the race is certain to get nasty in South Carolina.