The five presidential hopefuls who will take the stage tonight in Greenville before South Carolina's Republican faithful and a national Fox News audience aren't exactly the best-known folks looking to enter the race.

The debaters will be former Godfather's Pizza CEO Herman Cain; former New Mexico Gov. Gary Johnson; U.S. Rep. Ron Paul, R-Texas; former Minnesota Gov. Tim Pawlenty; and former U.S. Sen. Rick Santorum, R-Pennsylvania.

"By and large it's a pretty unimpressive posting," former Francis Marion University political scientist Neal Thigpen said shortly after the state party announced the names. "I'm not going to be surprised if the whole thing is underwhelming."

The better-known candidates considering a run, such as former Massachusetts Gov. Mitt Romney, former Arkansas Gov. Mike Huckabee, former Speaker of the House Newt Gingrich, former Alaska Gov. Sarah Palin -- even New York developer Donald Trump -- all opted not to show.

And that caused some disappointment for Berkeley County Councilman and County GOP Chairman Tim Callanan.

"Would I have liked more people who obviously have been traveling around the country to have committed to this? Yeah, I would have" he said. "It's important for us to get our message out what the Republican alternative is. They're giving up an opportunity to do that, which confuses me."

But Callanan said the lesser-known field could create a strategic advantage for the five candidates who do take part.

"It's a great opportunity for candidates who aren't getting a tremendous amount of press coverage to get their message out," he said.

Callanan also noted Gov. Nikki Haley's impressive come-from-behind win in last year's GOP gubernatorial primary -- a race where she beat three better-known challengers. "Where you start off in the polls ... is no longer indicative of where you're going to end up," he said.

Only Santorum has done much campaigning in South Carolina to date.

None of the five who will debate tonight registered above 3 percent during last month's Winthrop poll of 589 Republican and Republican-leaning South Carolina voters.

Former Louisiana Gov. Buddy Roemer, who has made a swing through the state, had hoped to take the stage but wasn't invited because he didn't hit the 1 percent mark in a national poll. Instead, he'll record his answers and stream them live on his website:

The 90-minute debate begins at 9 p.m. and will be televised live on Fox News channel.