WEST PALM BEACH, Fla. – Republican presidential front-runner Donald Trump on Saturday called on rival Marco Rubio to drop out of the White House race after the billionaire businessman won in Louisiana and Kentucky – and the Florida senator ended yet another election night with no wins.

“Marco has to get out of the race. Has to,” Trump said at a news conference at his golf club in West Palm Beach, Florida, where dozens of friends and club members mixed in with reporters covering his campaign.

Rubio finished no better than third in any of Saturday’s four Republican primary elections and caucuses. Meanwhile, Texas Sen. Ted Cruz won in Maine and Kansas.

Trump said that Rubio had “a very, very bad night,” and said that it’s time for the race to be a two-man contest between him and Cruz.

“You’ve got to be able to win. And he has not been able to win. And I think it’s time that he drops out,” he said of Rubio. “I would love to take on Ted one-on-one. That would be so much fun.”

Rubio’s campaign promptly rejected Trump’s call and continued to attack his business record and conservative credentials.

“Trump’s history as a con artist is being exposed,” said spokesman Alex Conant. “Trump knows that Marco has the momentum in Florida and is afraid because he knows losing those 99 delegates to Marco will be a turning point in this race.”

At his news conference in Florida, where Rubio is under intense pressure to win later this month, Trump also congratulated Cruz for his victories. But he joked that it’s natural that Cruz won Maine because “it’s very close to Canada, let’s face it.”

Trump has questioned Cruz’s eligibility to be president, because the Texas lawmaker was born on Canadian soil. Many legal experts have said that Cruz is a natural born citizen who is eligible to serve as president.

With 123 delegates, Rubio is 255 delegates behind Trump in the race for the 1,237 needed to win the Republican nomination for president. Trump is leading with 378, while Cruz has 295. Ohio Gov. John Kasich has 33.