Donald Trump's feud with Texas Sen. Ted Cruz may be headed to court. The real estate mogul threatened to challenge Cruz's eligibility to run for president "if he doesn't take down his false ads and retract his lies."
Because Cruz was born in Canada to an American citizen, U.S. immigration law says he earned citizenship as well. But the Constitutional mandate that the president must be a "natural born citizen" has not definitively been settled by the courts.
Trump told reporters he might try to file the suit before the GOP primary in South Carolina this weekend.
In a press conference on Monday, Trump called Cruz a "basket case" and slammed him repeatedly as a "liar."
Cruz responded at a campaign event that Trump had "apparently lost it."
"Have you noticed how rattled Donald gets when his numbers start going down? He gets very, very upset," Cruz said, according to The Associated Press. "But I guess the only explanation one can have is his internal poll numbers in South Carolina must be plummeting following the debate."