GOP frontrunner Mitt Romney appears to be headed for another win in the upcoming South Carolina primary as observers say a victory there would virtually seal the deal for him as the Republican presidential nominee.

Polls show Romney — who in national polls has a double-digit lead over other Republican contenders — also having a significant lead over his rivals in South Carolina, where state voters on Saturday will head to the polls in an open primary.

On Tuesday, Rasmussen Reports published a poll showing the former Massachusetts governor with a whopping 14-point lead over his challengers. He was favored by 35 percent of responders, despite speculation that his faith as a Mormon and his history as governor of a “blue” state would mean he wouldn’t fare well in the conservative state.

Former U.S. House Speaker Newt Gingrich was polling in second place with support from 21 percent of responders, while Rep. Ron Paul (R-Texas) and former U.S. Sen. Rick Santorum were tied for third with 16 percent. Texas Gov. Rick Perry had support from only 5 percent.

Hastings Wyman, who’s gay and editor of the Southern Political Report, predicted that Romney would win Saturday, and the South Carolina victory after previous wins in Iowa and New Hampshire would cement the candidate as the GOP nominee.

“From what I can see, it looks like Romney is going to win,” Wyman said. “And I think, assuming he does, the nomination is pretty much his. You never know what’s going to happen, but that’s what it looks like to me.”

Romney’s strong support in the polls was boosted by former Utah Gov. Jon Huntsman, Jr., dropping out of the race and endorsing Romney for president. Huntsman was polling in the single digits prior to his withdrawal, but his supporters likely went to Romney because of the endorsement and because both are seen as more moderate candidates in the Republican field.

GOProud Executive Director Jimmy LaSalvia, who endorsed Romney, also said he expects Romney to win and the race for the Republican nomination will virtually be a done deal after South Carolina.

“South Carolina voters have a history of voting for the eventual nominee,” LaSalvia said. “Mitt Romney will win in South Carolina on Saturday. There may be one or two of the other candidates who go on after losing on Saturday, but this primary election season will be effectively over.”

While campaigning in the Palmetto State, Romney has endorsed anti-gay positions. During a stump speech in South Carolina on Saturday, Romney said President Obama’s decision to discontinue the government’s defense of the Defense of Marriage Act in court would lead to the advancement of same-sex marriage throughout the country.

“This is a president also who is attempting to pave the way for same-sex marriage in our nation by refusing through his attorney general to defend the Defense of Marriage Act,” Romney said. “I will defend that act and I will also defend marriage as a relationship between a man and a woman.”

Romney has said he supports “full rights” for gay people, although he says he’s always opposed same-sex marriage. He has signed a pledge from the National Organization for Marriage committing himself to back a Federal Marriage Amendment, defend the Defense of Marriage Act in court and establish a presidential commission on “religious liberty.”

Even in a conservative state like South Carolina, Wyman said he doesn’t think opposition to gay rights will motivate voters to go to the polls because they’re more concerned about the economy.

“I don’t think it’s the leading issue,” Wyman said. “If one of the candidates were out-and-out pro-gay, then I think it would hurt him or her, but I don’t think it’s a big issue there.”

Fresh from his endorsement by evangelical leaders who threw their support behind him after a Texas meeting on Saturday, Santorum has also emphasized anti-gay views during his campaign, but has somewhat toned down his rhetoric.

“We need to encourage what is best for mothers and fathers and children, which is for them to be together and to give every child their birth right, which is to know and be loved by their mom and dad,” Santorum said. “If we don’t hold that up as something that society is for and encouraging and promoting, then we will get less of it and then we will be, in a sense, denying children what is best for them.”

Santorum was set to appear Thursday with Family Research Council President Tony Perkins at a Values Voters rally at East Cooper Baptist Church in Mt Pleasant, S.C.

Christine Johnson, executive director of South Carolina Equality, said LGBT people there have been watching the Republican presidential race as “day by day, the anti-gay rhetoric becomes increasingly part of the conversation.”

“It seems it’s not enough to campaign on foreign policy and the economy — the issues that affect us all — but necessary to include devisive language that not only contradicts their consensus building promises, but demonstrates an unapologetic view that the LGBT community should remain an undefined underclass of society,” Johnson said.

According to South Carolina Equality, more than 120,000 LGBT people are estimated to live in the state as well as more than 7,300 same-sex couples.

“This pandering to South Carolina, ultra-conservative voters, continues to disenfranchise the many LGBT Republicans that live in the Palmetto State and is creating both anger and resentment among the community at large,” Johnson said.