Exclusive: Bob Dole Endorses Marco Rubio in 2016 Race Dole says Donald Trump could secure the nomination on Super Tuesday.

 -- Former Republican presidential nominee Bob Dole is throwing his support behind Marco Rubio in the 2016 presidential contest after his early favorite – former Florida Gov. Jeb Bush – dropped out of the race on Saturday.

“Now that my good friend Jeb Bush is no longer running, I’m supporting Rubio,” Dole told ABC’s Jonathan Karl and Rick Klein in an interview for their new podcast “Powerhouse Politics” on Monday.

“He worked for my ’96 campaign in Dade County, Florida, and so I’ve had an acquaintance with him way back in ’96 when he was a hard worker. As much as I love John Kasich, you know, Rubio is probably a better candidate. And he’s young,” Dole added. “He wants to grow the party as opposed to [Ted] Cruz. I don’t know what he wants to grow.”

As Dole endorsed Rubio’s candidacy, the former U.S. senator from Kansas also warned of Donald Trump’s ability to win, saying he could secure the nomination if he sweeps the Super Tuesday states.

“Then I think you start printing the inaugural invitation,” Dole joked.

“If [Trump] has a good day on Super Tuesday, that's going to be hard to deny him the nomination. And if reality sets in and he's gonna start counting enough delegates, we've got to hope he'll be a good president,” he said.

“Trump has to start acting like a presidential candidate and tone down the rhetoric and don't insult anybody,” Dole continued.

Dole said that if Trump were to become president, the real estate mogul might “surprise” people with his performance, especially if he surrounds himself with qualified and experienced advisers.

“He's got to understand the presidency is -- it's an overwhelming position and you can't do it alone, and you gotta have qualified people with some experience. You can't bring in all the outsiders,” Dole said. “[Trump's] a pretty smart guy. He might surprise a lot of people.”

“I'd be happy to be his adviser,” Dole added.