Playing to the crowd in rough-and-tumble South Carolina, Republican candidates underscored their conservative toughness Friday as they plowed into the final stretch before the state’s first-in-the-South primary, hoping a win there would finally help one of them break out in the toss-up GOP field.

John McCain and Mike Huckabee were both predicting victory in South Carolina's primary Saturday, while Mitt Romney downplayed expectations, opting instead to campaign in Nevada ahead of its caucuses the same day.

All three have racked up a major win, and were looking for a bump to carry them through the Florida primary and Super Tuesday Feb. 5.; former Tennessee Sen. Fred Thompson, who has yet to win a state, is looking for new life in South Carolina.

Every eventual GOP nominee going back to 1980 has won the South Carolina primary, which could explain the spate of push polls and other negative campaign tactics coming out of the state.

Tune into FOX News and Foxnews.com for live coverage of the South Carolina primary Saturday. Polls open at 7 a.m. and close at 7 p.m. ET

Huckabee tried to brush off the dirty tricks in Greenville Friday, taking a moment to denounce push polls which have gone after his rivals.

"I hate push polling, I wish it didn't happen,” he said of pro-Huckabee calls being put out by a group called Common Sense Issues. “It certainly isn't happening with our permission, blessing or encouragement.”

Huckabee told FOX News Friday the state is not a “must-win,” but that he doesn’t plan to come in second. He also played up his Southern roots as a former Arkansas governor.

“I think I have a better understanding than anybody else running for president what unique challenges we face, not just in Southern states, but especially in Southern states,” he said in Bluffton, S.C. Friday.

Huckabee has tried to shore up support among conservative voters by recently signing a “no new taxes pledge” and another pledge against amnesty for illegal immigrants.

In an unexpected sideshow, Huckabee also curried favor with pro-Confederate flag advocates, who in one case began running radio ads against McCain and Romney for criticizing the flag. Huckabee said Thursday that South Carolina alone should make the decision over whether to fly the Confederate flag.

McCain, whose 2000 campaign unraveled after losing South Carolina, had already set up a group to fend off negative attacks in the state, spending his personal time stressing national security and the economy.

He blasted the federal government Friday for overspending at a time when South Carolina’s unemployment rate has hit 6.6 percent, the largest one-month increase in nearly 20 years.

"The economy is not good. The stock market continues down. And the indicators are not good. I'm not too astonished. ... We let spending get totally out of control, and it continues today, and I'm sorry to tell you this," McCain said at a town-hall style meeting at the Carolina Hospital East Campus in Florence.

McCain’s attention to economic factors comes after Romney aggressively pledged to fix Michigan’s “one-state recession,” which likely helped him win the Michigan State primary Tuesday. McCain earlier won the New Hampshire primary, while Huckabee won the lead-off Iowa caucuses.

Both Huckabee and McCain could play to a key South Carolina constituency: Huckabee, a Baptist pastor, to evangelicals, and McCain, a Vietnam veteran, to military families.

A new FOX News poll shows McCain holding on to his lead in South Carolina with 27 percent followed by Huckabee with 20 percent and Romney with 15 percent.

Click here to see the FOX News South Carolina poll.

But among those living in a military household, McCain has a double-digit advantage: 33 percent to Huckabee’s 18 percent and Romney’s 17 percent. Over half of likely Republican primary voters in the state live in a military household (52 percent).

Evangelical Christians were a key part of Huckabee’s win in Iowa and he retained a slight edge in that group in South Carolina, according to the poll. The former Baptist minister has a slim four-point edge: 27 percent Huckabee and 23 percent McCain. In Iowa, Huckabee won among evangelicals by nearly 30 points.

Almost two-thirds of likely voters in the South Carolina Republican primary describe themselves as evangelical Christians.

Thompson, who is hoping to revive his campaign in the state neighboring his own home state of Tennessee, received only 11 percent total in the poll, up just two points from earlier in the month. Thompson was running second in national polls after announcing his candidacy in September, but has slipped steadily since.

Thompson said Friday that “tomorrow night is very key for me. South Carolina … is the gateway to the rest of the country as far as I’m concerned, and we’ve been working very hard here and the response has been good, so we expect good results.”

He reiterated that he believes he’s the “strong, consistent conservative in this race.”

Thompson recently cast doubt on the need for the federal government to pass an economic stimulus package, as President Bush proposed Friday. And in Seneca, S.C., he made a point to defend the detention of prisoners at Guantanamo Bay.

Thompson even went after Huckabee Friday for saying in an interview that the Constitution is a “living, breathing document.”

“I thought it must have been Hillary or Obama (saying that),” Thompson said in Greenville. “I’ve come to find out it was Mike Huckabee. He apparently doesn’t know how that phrase has been used by liberals over the years …”

Meanwhile Romney left South Carolina for Nevada Thursday, sounding the same “Washington is broken” message he rolled out in Michigan.

Having said that McCain stands a good chance of winning South Carolina, Romney is the only major GOP candidate campaigning in Nevada.

Romney defended his strategy Friday in Reno, saying: " I love the entire country. I'm not leaving off any part of the country. I’m campaigning in 50 states, not in two or three ... Right now, we’ve had four contests and I’ve got two golds and two silvers. That’s a pretty good medal count if you’re an Olympian."

Romney also won the overlooked Wyoming caucuses, and former House Speaker Newt Gingrich told FOX News Friday that Romney’s strategy of focusing on racking up delegates is “giving him a real advantage.”

But some party officials have suggested that the GOP race is so close, it could come down to the Republican National Convention.

The Democratic South Carolina primary is Jan. 26.

FOX News’ Mosheh Oinounou, Serafin Gomez , Carl Cameron and Molly Henneberg and The Associated Press contributed to this report.