Romney, following a squeaker win in the Iowa caucuses and a convincing victory in the New Hampshire primary, leads the GOP pack in South Carolina by double digits, and has the money, organization and momentum going into its Jan. 21 primary, The Hill reported Wednesday.
The South Carolina GOP primary's history indicates the winner always wins the nomination.
But there are pitfalls to being a front-runner, the Romney campaign acknowledged.
"We knew coming here that Romney would have a bull's-eye on his back but now it's the size of the Target sign," said J. Warren Tompkins, a South Carolina GOP strategist advising Romney's campaign. "You've got to worry about that. We've got to survive here, but if you do the probability of getting the nomination is pretty good."
After wins in Iowa and New Hampshire, most political observers said a win in South Carolina likely would lead to a victory in Florida Jan. 31.
Former House Speaker Newt Gingrich and Texas Gov. Rick Perry are attacking Romney, prompting some Republicans to fret that the attacks will hurt his ability to win the general election against President Obama.
Perry and Gingrich have criticized Romney's time in the private sector as head of Bain Capital, with Perry saying Romney practiced "vulture capitalism."
An outside group led by a longtime Gingrich aide recently bought the rights to a documentary characterizing Romney as a "corporate raider" and plans to run trailers on it on South Carolina television, The Hill said.
"It's going to be devastating to Gingrich and his reputation," Tompkins said. "But the bigger factor is the president and [Obama adviser] David Axelrod and all of them in Obama-land are just going to be having belly laughs about this."