07/14/2016 14:15 EDT | Updated 07/15/2017 01:12 EDT

Donald Trump postpones VP pick announcement due to France attacks

After days of hype and speculation Donald Trump is finally set to unveil his running mate.

The presumptive Republican presidential nominee was expected to name his choice on Friday morning in Manhattan, but announced shortly after the deadly attacks in Nice on Thursday night that he would postpone the planned news conference surrounding the pick.

It's not known when the news conference will be rescheduled, but Trump will undoubtedly make the big reveal ahead of the Republican convention that kicks off Monday, where Trump is expected to be confirmed as the party's presidential nominee.

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Normally the vetting process for vice-president candidates is cloaked in secrecy but true to his preference for breaking with tradition, Trump has been conducting it more like his reality TV show The Apprentice. He's virtually auditioned potential picks out in the open in front of the media at campaign events and spoken freely about the qualities he's looking for and how many people he is considering. It seems he's whittled the contestants down to three.

On Thursday afternoon, some American media outlets were reporting that Indiana Gov. Mike Pence would be the likely winner of the contest, with NBC News going even further, reporting he was in fact the choice and had flown to New York to meet with Trump. 

But Trump's campaign was trying to tamp down the speculation, and the candidate himself told Fox News on Thursday evening to say he has not made "a final, final decision."

Trump and Pence campaigned together in Indiana Tuesday night then on Wednesday the two spent more time together at the governor's mansion, along with Trump's children who are influential advisers to their father's campaign. Another front-runner, Newt Gingrich, also flew to the state to meet with Trump that same day. He's also been in touch with Chris Christie by phone this week. 

Here's a look at the men who are in the running to be Trump's running mate.

Mike Pence

Pence is the current and first-term governor of Indiana. He has the legislative experience Trump is looking for, having spent 12 years in Washington in the House of Representatives. In Congress, he was not shy about clashing with Republican leadership. He brings a certain anti-establishment attitude, which Trump has campaigned on, yet he still knows how to work with people on Capitol Hill.

Pence calls himself an advocate for limited government, fiscal discipline, national defence and traditional moral values. He is a committed Christian and putting him on the ticket would appeal to that bloc of voters, some of whom question Trump's commitment to social conservative values. "I'm a Christian, a conservative, and a Republican, in that order," Pence is fond of saying. At the same time, Pence's social conservative credentials could alienate some independent voters whom Trump is trying to woo.

Pence is also an attractive choice for Trump because of his Indiana roots, which could help the New York businessman broaden his appeal nationally. Pence is a poster boy for small-town, rural America and his polite, Midwestern personality could balance Trump's larger-than-life one that turns off some voters. Pence would not give Trump any competition for the media spotlight.

The 57-year-old has been described as someone out of central casting for the role of vice-president and a safe choice.

Chris Christie

Christie, 53, is the New Jersey governor who ran against Trump for the nomination and dropped out early on in the primary season. It didn't take him long to jump on the Trump train and endorse his former rival over those left in the race including Ted Cruz, Marco Rubio and John Kasich. Everything negative Christie said about Trump while they were rivals was water under the bridge and now they get along great. His quick endorsement immediately had everyone thinking he was positioning himself for the VP shortlist, and that prediction turned out to be true.

His early support for Trump also got him a gig on the campaign, he was appointed to lead Trump's transition team should he win the November election. Term limits mean Christie isn't running for governor again so he'll be out of a job and perhaps eager to get one in the White House, whether as vice-president or a member of cabinet.

Christie's political resumé would help offset Trump's lack of experience and he's got the brash, attack-dog personality that Trump at one time said he'd like to have in a running mate.

Despite Trump and Christie having a good personal relationship, American media are reporting that Trump's son-in-law Jared Kushner is blocking the idea. When Christie was a state prosecutor he helped put Kushner's father in jail over tax evasion and other charges. Kushner has been an influential adviser to Trump on the campaign so that could be a problem for Christie.  

Newt Gingrich

Speculation that Gingrich could be Trump's VP pick ramped up earlier this week when Fox News cut ties with him. He had been a regular contributor on the network. If Gingrich gets the nod, it would be a huge comeback for the former congressman and Speaker of the House of Representatives who left Capitol Hill in 1999 amid controversy and in the wake of ethics investigations into his conduct. He would bring a lot of baggage with him to the White House. He tried and failed to get back into Washington when he ran for the nomination in 2012.

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He would bring his many years of Washington experience to the table (he was first elected in 1978) and Trump wants someone who knows how Congress works and can act as a bridge to the Republican establishment. His personality is not unlike Trump's — it's big. Is there room on the ticket for two similar temperaments or will Trump pick someone lower key who won't overshadow him?

Since he endorsed Trump in the spring, Gingrich has been a high-profile and effective surrogate. If he were Trump's sidekick he's seen as someone who could ably make the case to voters for a Trump presidency.

His age, 73, could be a strike against him. Trump is 70 so that would make for an older ticket compared to picking Pence or Christie.