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MIAMI (CBSMiami) – Republican presidential hopeful Ted Cruz got a new endorsement Thursday ahead of the Republican debate in Miami.

Sen. Mike Lee from Utah endorsed Cruz on Thursday afternoon.

“There is a difference between slogans and substance. Ted is that difference,” said Lee. “He is the only Republican candidate who can defeat Donald Trump, who can defeat Hilary Clinton. And I believe he will.”

Lee’s endorsement is substantial because one he is a Tea Party favorite. It also helps because he didn’t endorse Sen. Marco Rubio – like countless politicians have thus far.

Former GOP presidential candidate Jeb Bush met with Cruz, Marco Rubio and Ohio Gov. John Kasich, but not Trump. It’s unclear why Bush met with the three contenders, but the fact that he did not meet with Trump signaled he was trying to strengthen any efforts that could bring down the GOP front-runner.

Bush’s brother, Neil, has signed on with Cruz’s campaign.

The announcement comes as the four remaining Republican presidential candidates are set to square off in their 12th debate Thursday night at the University of Miami.

On Wednesday, two of the four staged rallies in South Florida to drum up support.

Dubbed by some pundits as running a ‘shrinking campaign,’ Sen. Marco Rubio is fighting to stay in the race.

Hoping for home state advantage, Rubio trailed front-runner Donald Trump by 23 points in the latest Quinnipiac University poll released Wednesday.

At a rally in Hialeah’s Milander Stadium Wednesday night, Rubio addressed the rumors that he would drop out of the race.

“I will be on that ballot on Tuesday. I will campaign as long and as hard as it takes. We are going to the White House. We are going to win this nomination,” said Rubio amid cheers.

Mobbed by long time supporters on the way out, Rubio underscored his resolve.

“We are going to work it really hard all the way through to Tuesday and I think we will be successful. Polls are polls,” said Rubio.

Rubio and his GOP opponents know a loss next Tuesday in Florida would most likely force him out of the 2016 contest.

“This is do-or-die for Rubio,” said die-hard supporter Jim Wilson, who follows the young senator’s campaign across the country in his pickup truck.

And the chairman of Florida’s Republican Party refused to call Rubio out, but expressed regret over what’s happened thus far with Bush out.

“We knew that the field was going to narrow. It would have been great if some of our favored sons would have been in it,” said Blaise Ingoglia.

Cruz who also held a rally in South Florida on Wednesday and said the race will come down to only two candidates – and he’s one of them.

“Conservatives are uniting with us and as this race continues to narrow to two man race, head to head Donald Trump loses,” Cruz told the cheering crowd.

Cruz also put emphasis on his Cuban roots.

“My dad was imprisoned and tortured in Cuba,” Cruz told the gathering. “His Cuban heritage is so much a part of his heart and soul. So where better to talk about that heritage than here, where he has so many kindred spirits.”

Cruz’s talk about his Cuban heritage may be paying off.

A Bendixen & Amandi International poll released Thursday shows overall, Trump leads among likely Republican Presidential Primary voters in Florida with 38 percent, followed by Rubio with 31 percent and Cruz with 19 percent.

Ingoglia attributes Trump’s success to tapping into a frustrated voter base.

“Well what I would say to that is Donald Trump has obviously tuned into something that is going on within the Republican base,” he said. “Look, a lot of republicans are frustrated. They are frustrated with what’s going on in Washington, D.C. They are frustrated with the last eight years and the lack of leadership Barack Obama and they want some things to change.”

However, among Latino voters the numbers shift dramatically.

The poll shows Rubio surging to 49 percent support among Hispanic Republicans, followed by Cruz with 21 percent and Trump with 19 percent.

A surprise visitor made an appearance to support Cruz – his former rival Carly Fiorina.

“I say to you it is time. It is time to take our party back,” said Fiorina. “It is time to take our government back. It is time to take our country back and so it is time now to unite behind the one man who can beat Donald Trump, who can beat Hillary Clinton, who can beat the D.C. cartel.”

As for Rubio, she asked the crowd, “Why not endorse Florida Sen. Marco Rubio, what did you feel he was lacking?”

She went on, “Marco Rubio is a good man but he, in my view, is not the conservative we need in the Oval Office.”

Fiorina went on to compare GOP front-runner Trump to Democratic front-runner Hillary Clinton.

“The truth is that Donald Trump and Hillary Clinton are two sides of the same coin. They aren’t going to reform the system. They are the system,” said Fiorina.

Trump, speaking to CNN’s Anderson Cooper, said he’s going to take both Florida and Ohio next Tuesday.

“You think you’ll get all the delegates,” asked Cooper.

“I think so, yeah. I really think so. I don’t see the convention going that route. I see– I see probably getting the delegates. You know, it’s like the fighters,” replied Trump. “That’s the ultimate way of doing it. You knock ’em out. If you knock ’em out, nothing can happen.”

Gov. Kasich, who has been notably absent in Florida, is instead focusing his efforts on winning his home state of Ohio.

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