Many have speculated that former Massachusetts Gov. Mitt Romney can't win South Carolina, but the latest polls show that he's in the lead.

Despite a surge from Sen. Rick Santorum following his performance in Iowa, Romney led all three polls released Thursday.

Polls have varied greatly during the race for South Carolina, and that trend will likely continue. During 2008, John McCain stood fourth in early January polls before eventually winning the primary.

Update: CNN/Time/ORC Poll Shows Romney Holds Large Lead

A poll released Thursday by CNN shows former Massachusetts Gov. Mitt Romney with his largest lead yet in South Carolina.

According to the poll, Romney holds 37 percent support from likely Republican voters. His nearest opponent, Sen. Rick Santorum, earned 19 percent support and former House Speaker Newt Gingrich earned 18 percent.

The poll reflected a big change from polls released earlier Thursday, which showed Romney with much slimmer leads.

The results from those polls are summarized below.

Originial: Polls Say Santorum Surges, Romney Regains SC Lead

A Rasmussen poll of likely primary voters shows Romney at 27 percent, with Santorum just behind at 24 percent. Former House Speaker Newt Gingrich, who held a significant lead in the last South Carolina poll, has slipped to third place at 18 percent.

In an American Research Group poll, Romney's lead is slightly larger, as 31 percent of respondents supported him. Gingrich and Santorum were tied at 24 percent.

Romney's lead in South Carolina is smaller than his lead nationally, where he holds 29 percent support as compared to Santorum at 21 percent.

Gingrich leads among male voters, with 34 percent support, while Romney holds a one-point lead over Santorum among women with 31 percent support.

The race for South Carolina remains fluid, as it did during 2008. According to the Rasmussen poll, only 41 percent of likely voters know who they will vote for, while 48 percent said they could change their minds.

Rasmussen's summary also notes:

In 2008, during the final week leading up to the South Carolina primary, voters for less successful candidates peeled away from their first choice to vote for one of the two front-runners. In that race, it was the eventual nominee John McCain and the second place finisher Mike Huckabee.

A similar result could be expected during 2012, as South Carolinians hope to extend their streak of accurately choosing the GOP nominee.

Interestingly, 66 percent of South Carolinians think Romney will win the nomination, while only 11 percent think Santorum will win and nine percent picked Gingrich.

The Rasmussen survey, conducted Thursday, asked 10 questions to 750 likely South Carolina primary voters and includes a 4 point margin of error.

Evangelical Christians, an important segment of the South Carolina electorate, said they preferred Santorum (33 percent) to Romney (17 percent). Protestants and Catholics, however, were more likely to support Romney.

More than 80 percent of those surveyed said they would vote for the eventual Republican nominee against President Obama even if their preferred candidate didn't win. Six percent said they would vote for Obama if their preferred candidate failed to win the nomination.