Former Florida Gov. Jeb Bush, after ending his campaign last month, is returning to the 2016 fray to meet with the remaining not-Trump candidates in his home state on Thursday – potentially the first step in an effort to power-broker a consensus alternative to take on the Republican front-runner.  

It’s unclear whether Bush plans to endorse anyone before Florida holds its all-important primary on Tuesday. But the former candidates sense a quickly closing window to pick their horse as Donald Trump racks up ever-more wins and delegates.

Another former candidate, ex-HP CEO Carly Fiorina, announced her endorsement earlier Wednesday for Texas Sen. Ted Cruz during a surprise appearance in Miami.

Fiorina, who dropped out of the 2016 race in February, called Cruz a “leader and a reformer” and urged voters to rally around Cruz as the candidate who can challenge Trump.

“Donald Trump and Hillary Clinton are two sides of the same coin. They’re not going to reform the system. They are the system,” she said.

Sources confirmed to Fox News that Bush plans to meet Thursday with Cruz, Florida Sen. Marco Rubio and Ohio Gov. John Kasich while the candidates are in Florida for a GOP debate Thursday night. He has no plans to meet with Trump.  

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Asked about the meeting, which was first reported by The New York Times, Kasich told reporters he doesn’t know Bush’s plans and whether he intends to endorse.

“I like Jeb. I’ve known him a long time. And I don’t try to pre-guess what’s going to happen in a meeting,” Kasich said, adding: “Of course I’d like his endorsement. I’d like everybody’s endorsement.”

The movement by former GOP candidates comes after Cruz walked away from Tuesday’s primary contests with just one win, in Idaho, compared with Trump’s three. The billionaire businessman won in Mississippi, Michigan and Hawaii, building his already substantial delegate lead over the field.

New Jersey Gov. Chris Christie, another former presidential candidate, already has announced his support for Trump, taking to the campaign trail to stump with him.

But Fiorina railed against Trump during her pep talk for Cruz on Wednesday. And it’s hard to imagine Bush would even contemplate backing Trump’s outsider bid.

While Bush was in the race, Trump was relentless in his criticism of Bush’s family, his “low energy” and the big-money super PACs supporting him – which could explain why Bush does not have plans to meet with Trump in Florida on Thursday.

In her remarks in support of Cruz, Fiorina argued Wednesday he’s the only GOP candidate who can beat primary front-runner Trump or Clinton.

Fiorina said the argument that Cruz has made too many enemies on Capitol Hill only proves he is taking on the “Washington cartel.”

“You have a very important job on Tuesday,” said Fiorina, referring to Florida’s primary, where Cruz is running behind Trump. “It’s time to take the party back. It’s time to take our government back. It’s time to take the country back. So it’s time to unite behind the only one who can, Ted Cruz.”

Florida Sen. Rubio, who has only won two contests to date, has vowed to come from behind to win his home state next week, though he, too, trails in the polls. 

Fox News’ Hillary Vaughn and Dan Gallo contributed to this report.