Next key tests in White House race today

White House hopefuls face their third test today when Republicans square off in South Carolina with Donald Trump enjoying a commanding lead, and Democrats battle in Nevada where Hillary Clinton is seeking a comeback.

As the race moves on, the two parties are on separate battlefields. In South Carolina, Republicans will vote in a primary, while in Nevada, Democrats will caucus — grouping themselves together by candidate to voice their support.

Trump is looking for a big symbolic win ahead of "Super Tuesday" — March 1, when about a dozen states will go to the polls, with a quarter of the nominating delegates up for grabs.

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"It's crunch time, folks," Trump, 69, told voters at a North Charleston rally, his final pitch before the South Carolina primary.

The real estate billionaire finished second to Senator Ted Cruz in Iowa on February 1, but secured a commanding win in New Hampshire one week later.

Trump took no chances yesterday, urging all of his supporters to troop to the polls.

"I don't want your money," added Trump, who is self-funding his campaign. "We want your vote."

Trump – the onetime reality TV star who has upended the political landscape with his brash style and controversial comments on everything from Muslim immigrants to waterboarding – has his eye on a particular date: March 15.

On the eve of the primary Trump led with about 28% of likely Republicans voters backing him, according to an NBC-Wall Street Journal poll.

The ultra-conservative Cruz followed with 23%. Trailing were Senator Marco Rubio at 15% and former Florida governor Jeb Bush at 13%.

Rubio and Bush are under intense pressure to fare well, as is Ohio Governor John Kasich and retired neurosurgeon Ben Carson, whose campaign has struggled to gain traction.

To the west, Democrats were making their closing arguments in Nevada, land of the desert sun, for Saturday's caucuses.

The key issue is the minority vote: blacks, Hispanics and Asian Americans make up roughly half of the state's population.

Clinton, who won by a hair in Iowa and lost big to rival Bernie Sanders in New Hampshire, is counting on a major Hispanic voter turnout, especially among the hotel and casino employees in Las Vegas.

Since Wednesday, the former secretary of state, 68, has visited staff at Caesars Palace, the MGM Grand and the Paris casinos, in order to persuade them to join her camp.