DAVID GREENE, HOST:
With those stakes high in South Carolina, the political ads are getting more pointed.
As NPR's Brian Naylor reports, the candidates themselves are taking aim less at each other and more at the White House.
BRIAN NAYLOR, BYLINE: The day before the South Carolina primary, the remaining Republican candidates are making their final TV pitches to voters. Here's part of what the Mitt Romney campaign bills as its closing argument.
(SOUNDBITE OF A POLITICAL ADVERTISEMENT)