David Jackson

USA TODAY

SANTEE, S.C. — First, South Carolina — then the nation?

Donald Trump seems to think so.

The New York businessman and Republican front-runner is poised to win the South Carolina primary on Saturday, and he says a big victory in the Palmetto State will open the road for him to take the GOP presidential nomination. "If we win in South Carolina, we feel we could run the table," Trump told a crowd of cheering supporters in Walterboro, a line he has repeated throughout the state this week.

Some political analysts are skeptical, as are Trump's Republican primary rivals: Ted Cruz, Marco Rubio, Jeb Bush, John Kasich and Ben Carson. All are chasing Trump across South Carolina and the country, each hoping for an eventual one-on-one showdown with the front-runner, starting with a surprise showing in South Carolina.

While Trump leads Palmetto State polls and most national surveys by wide margins, opponents point to evidence that his support could be softening. A NBC News/Wall Street Journal poll out Wednesday gave Cruz a slight lead over Trump among Republicans nationally, 28% to 26%. Rubio was third at 17%, followed by Kasich (11%), Carson (10%) and Bush (4%).

"There's a new national front-runner in the Republican race," the Texas senator told South Carolina supporters this week.

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Rubio, a senator from Florida, made appearances in South Carolina with two prominent endorsers in tow: Gov. Nikki Haley and Sen. Tim Scott, both of whom cited the state's past history of picking eventual Republican nominees. "We make presidents,” Haley told Rubio backers.

Like South Carolina primaries of the past, this one has seen its share of political attacks and alleged dirty tricks. Trump has threatened to sue Cruz over his eligibility to be president, citing his birth in Canada. Cruz told Trump to bring it on, saying his mother was a U.S. citizen. Trump and Cruz have accused each of lying about the the other. So have Cruz and Rubio.

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The New York businessman also found himself embroiled in a dispute with none other than Pope Francis, who said Trump's proposal to build a wall along the U.S.-Mexico border is un-Christian.

Bush, a former governor of Florida, is also among those pursuing Trump in South Carolina. With the backing of veteran South Carolina Sen. Lindsey Graham, Bush has told crowds that Trump is not a conservative and is only trying to "hijack" the Republican Party for his personal use.

Carson and Kasich are considered long shots in South Carolina. Kasich, the Ohio governor who finished second to Trump in the New Hampshire primary, also campaigned this week in Michigan, preparing for a series of Midwest primaries next month.

Trump is also looking ahead. During his travels in South Carolina, Trump cited his big poll leads in Nevada, which hold caucuses on Tuesday, and in a group of Southern states that hold primaries on March 1.

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The billionaire's "run the table" strategy has been questioned by political analysts who said Trump is doing well in part because opponents are splitting up what appears to be a considerable anti-Trump vote — a situation that will change as challengers drop out, as is expected after South Carolina.

David Woodard, a political science professor at Clemson University, said Trump seems to be drawing from one part of the Republican voter stream, while his opponents are all drawing from another. "As the field narrows, he'll begin to dip and they will begin to rise," said Woodard, who is also a Republican consultant but has not endorsed in the presidential race.

For decades, South Carolina Republican prided themselves on picking the party nominee. The winners of the South Carolina primary eventually took the GOP nomination in 1980 (Ronald Reagan), 1988 (George H.W. Bush), 1996 (Bob Dole), 2000 (George W. Bush) and 2008 (John McCain).

Then came 2012. Newt Gingrich, from neighboring Georgia, won South Carolina but soon fell from contention overall.

Scott Huffmon, a political science professor at Winthrop University in Rock Hill, S.C.,said the 2012 primary may have been "a canary in the coal mine" anyway — Gingrich practiced the kind of anti-establishment politics that have dominated the 2016 election, and propelled Trump. "Now the entire nation of conservative voters is voicing their anger at the Republican establishment," he said.

Trump is the tribune for many of those voters. A South Carolina win would not automatically make Trump the nominee — certainly not mathematically — but makes it more of a challenge for rivals to catch him. "The chances get harder and harder with every win," Huffmon said.

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