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With the South Carolina primary five days away, the tea party movement has accelerated its efforts to leverage what is likely its last opportunity to influence the Republican nomination process.

The movement has thus far struggled to coalesce behind one candidate. Despite Mitt Romney's victories in the Iowa caucuses and New Hampshire and endorsements from the likes of conservative South Carolina Gov. Nikki Haley, he has yet to win the support of the elusive tea party.

Many in the grassroots movement vehemently oppose the former Massachusetts governor, who they deem to be no different than President Obama, politically and ideologically. In a poll conducted by Judson Phillips, founder of the Tea Party Nation, 40 percent of tea partiers said they would not vote for Romney in the general election.

"Romney is not a moderate. He is a liberal. He is almost as far to the left as Barack Obama," Phillips, who organized the first tea party convention in February 2010, said. "Had Obama been governor of a state, his policies would've looked identical to what Romney's looked like when he was governor of Massachusetts."

The tea party movement has a strong presence in South Carolina. Only four percent of those surveyed in a November poll by Clemson University opposed the conservative movement, and many in the movement see South Carolina as the last frontier to make a concerted effort to derail Romney's candidacy.

"If he wins here, it's game, set, match Romney," author and Clemson University professor David Woodard said.

At a major convention held by the Tea Party Patriots this weekend, Romney was notably missing from the list, which featured candidates Newt Gingrich and Rick Santorum and GOP heavy hitters such as Haley and Sen. Jim DeMint.

The Republican senator from South Carolina who has emerged as a tea party star told ABC News Friday that Romney needs to work on his empathy.

"I know I had to do it a few times in my career and I had sleepless nights and it killed me to do it, but I was doing it to save the other employees in my company and keep it going," DeMint, a former marketing consultant, said. "If he doesn't explain this, well, he's going to see this again if he's the nominee in the general election."

But the biggest trouble for the tea party movement is the failure to unite behind one candidate, in many ways hurting the movement that already lacks a cohesive leadership. "The tea party is so fractured and we are so independent … that by the time we have one conservative left standing, it may too late," said Phillips, who has endorsed Gingrich.

And that, Phillips added, could hurt the Republican Party in November. Grassroots momentum by tea party activists helped propel many first-time candidates into Congress in 2010, and the Republican party will need that to ensure a win.

"Worst-case scenario, we find a candidate whose a third-party candidate. That means Obama would get a second term. We realize that but Romney is little better than Obama," Phillips said. "A Romney nomination is a lose-lose scenario for the tea party. We'll have Obama in the White House for a second term or we'll have a liberal in the White House. There is very little upside to that."

But it is going to be a tough task. Even tea party sympathizers have hinted at a Romney candidacy. Haley, who surged to the governorship with tea party support, endorsed the former governor, upsetting many of her supporters. Freshman Rep. Tim Scott, who rode the same wave to Congress, also acknowledged there's a divide among conservatives.

"When you have Rick Perry, when you have Mr. Santorum, Mr. Gingrich all working on the social conservative platform in South Carolina, you see there is a divide on the social conservative side," Scott said in an interview with CNN's John King last week. "So I think it's going to be very difficult for any of us to find one candidate that becomes the anti-Romney candidate in the next nine days."

Since the movement's ascent in 2010, some tea party fans believe its influence is fading. It has been less visible in the 2012 election scene and has been in some ways overshadowed by the leftist Occupy Wall Street movement. Unlike three years ago, the movement has also been less visible on the national circuit, with virtually no gatherings to boast of in Washington D.C.

"It is almost impossible to believe and downright sickening to accept that in light of the clear mandate of the tea party that the GOP stands on the cusp of returning to 'establishmentarianism,'" wrote conservative columnist and radio talk show host Kevin McCullough. "But it appears that for all the big talk, tens of thousands of local rallies, and the single largest non-inaugural event to ever occur on our nation's mall, the tea party has died. Which is sad. And it's sad for me personally as a supporter, because I believed in the movement and I even addressed those patriots, on that mall, that cloudy Washington day."

Tea Partiers, however, charge that although they might not be able to influence the presidential race as much as they had hoped, they still plan to make a dent in this year's state and congressional elections.

"There are several people interested in the presidential election," said Shelby Blakely, executive director of The New Patriot Journal, a publication of the tea party Patriots, "but there is a larger group that's focused on the congressional election in 2012 and to continue to elect tea party-minded individuals within the U.S. Congress."