NEW YORK (CBSNewYork)Donald Trump may have prevailed in the New Hampshire, but he’s heading into a tough primary in South Carolina next week.

On Friday, he pulled, well, a “Donald Trump,” which naturally began with a tweet that was not so sweet, this time aimed at Texas Sen. Ted Cruz, CBS2’s Marcia Kramer reported.

“If @TedCruz doesn’t clean up his act, stop cheating, & doing negative ads, I have standing to sue him for not being a natural born citizen,” Trump tweeted.

Trump revived a charge he made earlier in the campaign that Cruz is ineligible to be president because he was born in Canada. Cruz says he is eligible because his mother was a U.S. citizen at the time of his birth.

On Friday, Cruz was just intent on piling up votes.

“The men and women in this room have the ability to change the outcome of the South Carolina primary,” he said during a campaign stop.

Other Republicans, meanwhile, concentrated their firepower on Trump.

“Negotiating a hotel deal in another country is not foreign policy experience,” said Florida Sen. Marco Rubio.

Former Florida Gov. Jeb Bush described Trump as “a entertainer, a guy who’s a reality-TV star, who has been successful in his own life but he also pushes people down to make himself look better.”

In the Democratic contest, both Hillary Rodham Clinton and Bernie Sanders are trying to send a message to African-American voters, who make up a large percentage of the South Carolina electorate, that they are the rightful heir to President Barack Obama.

“Sadly in America today, in our economy, a whole lot of those poor people are African-American,” Sanders said during Thursday night’s debate.

“The Affordable Care Act has helped more African-Americans than any other group,” Clinton said.

Both Democrats are embarking on a big media war in key states.

Team Clinton has reserved air time in 17 states beyond the next two contests in South Carolina and Nevada. She’s going to spend $27.7 million, just shy of the $28.4 million Sanders will concentrate in just six states.