Palin supports Gingrich

Sarah Palin

COLUMBIA -- Sarah Palin said that if she lived in South Carolina, she would vote for Newt Gingrich in the state's presidential primary.

The former Alaska governor and vice presidential candidate told Fox News on Tuesday that she wants to see the Republican nomination fight continue.

Palin said the GOP candidates are improving as the contest continues and added that, in her words, "iron sharpens iron and steel sharpens steel."

Palin considered entering the presidential race last year but decided not to. She still holds sway among tea party activists. Palin was the GOP's vice presidential candidate in 2008.

Earlier in the day, Gingrich leveled a forceful new attack on Mitt Romney, calling the GOP front-runner's former private equity firm "exploitive."

The former House speaker had attacked Bain Capital before, but his comments before a gathering of business leaders in Columbia contained some of his harshest rhetoric yet and came just four days before the South Carolina primary, a critical benchmark for the Gingrich campaign.

Gingrich was holding little back in his criticism of Romney, saying that, in at least some instances, the Bain model has meant "leverage the game, borrow the money, leave the debt behind and walk off with all the profits."