What to Watch for at Tonight's GOP Debate

— -- Six Republican presidential candidates will turn on their Southern charm as they take the debate stage in Greenville, South Carolina, on Saturday night.

The debate, hosted by CBS News and the Wall Street Journal, will be the first time the candidates have squared off since the New Hampshire primary.

Here are the five things to watch for Saturday night – and for the final week before the Palmetto State’s GOP primary:

1. Which Trump Will Show Up?

Less than a week after a resounding win in New Hampshire, Donald Trump is exuding confidence (the latest polls show him with the lead in South Carolina), and he has been modulating his message – sometimes on the attack, sometimes staying positive.

His campaign, for example, pulled a negative ad attacking main rival, Texas Sen. Ted Cruz, Wednesday.

“We have a country that we’re proud of and we love and we’re not going to lose,” Trump recites in the positive spot.

On the campaign trail – and on social media – however, it’s a different story.

So, the first big question for Saturday night is: Which Trump will show up?

2. Marco Rubio Gets Gritty

On his way to South Carolina after his disappointing finish in New Hampshire, Marco Rubio told ABC News' Jonathan Karl that at last Saturday’s debate, he elected not to attack his fellow Republicans and instead focus on President Barack Obama.

“In hindsight,” Rubio admitted, “maybe that was a mistake.”

To wit, Rubio has spent the last few days in the Palmetto State going on offense, shooting attacks in the direction of Trump, Cruz and Jeb Bush in particular.

He accused Bush of having “no foreign policy experience, period” and called Cruz someone who will “say or do anything to get elected.”

Looks like Rubio won’t be pulling his punches on debate night.

3. Kasich Courting South Carolina

Riding high from his surprise second place finish in New Hampshire, Ohio Gov. John Kasich is dealing with the reality that South Carolina voters don’t know him as well because he spent so much time focused on the Granite State.

An NBC News-Wall Street Journal poll released Jan 28. shows Kasich with one percent of support from South Carolina voters.

As for his debate strategy tomorrow night, Kasich might take the approach of not attacking other candidates as he says he does on the campaign trail.

However, his campaign has been targeting Bush, calling the Florida governor out for negative ads he’s been running.

"I’m not gonna be a pincushion or a marshmallow, but I’m also not gonna spend my time trying to trash over people," Kasich said earlier this week while introducing himself to Charleston, South Carolina, voters.

4. Keeping Up With the Bushes

Right before the New Hampshire primary, Jeb Bush received a boost when his mother, former First Lady Barbara Bush, joined him on the campaign trail. In order to win South Carolina, the Bush campaign is pulling out all the stops and that includes unveiling another secret weapon: George W. Bush.

The former president is scheduled to appear alongside his brother at an event in North Charleston on Monday.

Will George W.’s efforts help Jeb?

Matt Moore, chair of the South Carolina Republican Party, argues it "could."

“George W. Bush is well liked in South Carolina,” Moore said Wednesday at an event hosted on Sidewire to discuss the upcoming primary. “Both George W. Bush and his father won huge primary victories here in 2000 and 1988, respectively.”

5. Things Are Looking South for Carson

The former neurosurgeon just barely met the requirements to be on stage at tomorrow night’s debate. An NBC News-Wall Street Journal poll released last month showed Ben Carson polling at eight percent in South Carolina.

Carson placed fourth in the Iowa caucuses but he slipped in New Hampshire, winning only about two percent of the vote.

One final question heading into the debate and the week ahead: Could tomorrow night could be Carson’s last debate and could South Carolina be the end of the line for his campaign? Only time will tell.

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