Updated 9:45 p.m.

Donald Trump will unveil his running mate on Friday morning, he announced via Twitter this evening.

The deadline for a decision comes after the presumptive GOP presidential nominee wrapped up both public tryouts and private meetings with the three men believed to be among the finalists — Indiana Gov. Mike Pence, former House Speaker Newt Gingrich and New Jersey Gov. Chris Christie.

After he campaigned with Pence in Indiana Tuesday evening, Trump his family met with Pence at his Indiana home on Wednesday morning, according to NBC News, while Gingrich and Alabama Sen. Jeff Sessions also flew to Indianapolis to meet with Trump. Christie met with Trump and his family on Tuesday.

Pence, who gave a tepid endorsement to Texas Sen. Ted Cruz before his state's primary, was more gleefully on board with Trump's campaign on Tuesday night as he introduced him at a rally in Westfield.

"Donald Trump gets it," Pence told the crowd. "Donald Trump hears the voice of the American people."

"We are ready to put a fighter, a builder and a patriot in the Oval Office of the United States of America," he continued.

Of the three presumed vice presidential finalists, Pence was the only one who gave a direct introduction for Trump before he came to the stage. Trump also campaigned with Christie on Monday in Virginia and with Gingrich last week in Ohio.

Trump praised Pence at the end of what was a meandering speech — attacking rival Hillary Clinton often but also wandering off into other topics such as immigration and trade and back again.

"I don't know if he's going to be your governor or your vice president, who the hell knows!" Trump told the crowd, referring to Pence.

Trump has held tryouts of sorts for each of his potential picks, and the process he seems to be using has drawn more than one comparison to the reality TV world that boosted Trump ahead of his presidential run.

Gingrich predicted the pick would come Wednesday or Thursday, telling Fox News, "It's a little bit like The Apprentice. You find out sooner or later who the last one standing is."

Pence is an attractive choice for several reasons — he has both executive and congressional experience, something Trump has said he is looking for in a potential running mate.

But he also has plenty of baggage as well. Around Indianapolis, yard signs that read "Pence must go" can be seen in front of some houses. He is locked in his own re-election battle back in the Hoosier State, and joining Trump's ticket could give him an out from a tough race. Indiana law bars him for running for both offices, and the deadline to withdraw is Friday.

Once a hero of social conservatives, Pence ran into controversy last year for a "religious freedom law" that would have allowed individuals and corporations to cite their religious beliefs as a reason to refuse goods or services. Major businesses in the state revolted and threatened to leave, and Pence signed a revised version that he argued would narrow the possibility that LGBT individuals would face discrimination under the law.

That episode saw him fail to defend the original law — which was cheered by many evangelicals and religious conservatives — on a national stage. And when he signed the new law, many were subsequently upset he bent to pressure so quickly.

Tony Perkins, president of the conservative Family Research Council, told NBC News that he believed Trump could "do better" with a pick " who has not capitulated on something as fundamental as religious freedom."

Tony Zirkle, an attorney from Crown Point, Ind., who was at the rally Tuesday, said he liked Pence but that Trump might see his social conservatism as a liability.

"Honestly, the homosexual lobby is too strong; he's not gonna pick Pence because he made them angry, but it's nice that he's considering him," Zirkle said.

Trump continues to drop other breadcrumbs about whom he might choose. In an interview with the Wall Street Journal on Tuesday, he said he was looking for someone who would be an attack dog and "fighter skilled in hand-to-hand combat" to rebut criticisms from the media. That's something he said he finds in both Christie, the first of his former rivals to endorse him, and Gingrich.

Pence probably said all the right things on Tuesday, but he didn't come off as pugnacious as both Gingrich and Christie often can.

Trump is also closer to Gingrich and Christie, having campaigned with both several times already. Trump first spent time with Pence and his wife over the Fourth of July holiday and said he walked away impressed.

Ultimately with Trump, trying to read the tea leaves of whom he might pick or what he might do this election cycle has proved futile.

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