The top contenders were told to expect a decision as early as Thursday afternoon.
All four of Mr Trump's children and his wife Melania will speak at the convention, as will Speaker of the House Paul Ryan, House Majority Leader Kevin McCarthy and Senate majority leader Mitch McConnell.
Trump is expected to make an official announcement Friday at 11 A.M.
Late Thursday, a truck drive onto the sidewalk and plowed through a crowd of revelers who'd been gathered to watch Bastille Day fireworks in Nice, France.
The New York Times was the first to report about it. Their sources saying the Indiana Governor has accepted. And with Hillary Clinton's campaign faltering badly, Trump didn't give anyone an excuse to attack him for an off-the-wall selection.
The Pence campaign has all the paperwork prepared and ready to file in order to meet the deadline in case he is tapped by Trump.
Fortenberry said he knows the governor well having served alongside him in the House and particularly on the House Foreign Affairs Committee. Pence would help reassure conservatives, who have had their doubts about Trump, about what kind of president he would be.
He has influential allies in Trump's inner circle.
Statements from Trump's advisers show a campaign team that is playing its cards very closely to its chest, mainly focusing on the timing of tomorrow morning's announcement, but not hinting at whom Trump's choice of vice president may be.
The long-awaited decision upends the political landscape in IN and at least partially remakes the Trump campaign in Pence's image.
All three of the finalists have had extensive conversations with Trump and his family in recent days.
"Most of the rest will come around".
Trump was in California Thursday for several fundraisers. State law prevents someone from seeking two offices at once. He has until Friday at noon to officially withdraw from the gubernatorial race. That's according to a person familiar with Trump's thinking, who spoke on condition of anonymity because the person was not authorized to discuss the vetting process. However, those documents have not been filed. He added, "I think he'll consistently make good decisions".
Gingrich was the most visible of the contenders.
"He fills in a lot of the blanks on the social conservative side of this", King said of Pence. But the move alienated some moderates in the party.
Pence introduced Trump at a rally in Westfield on Tuesday night and Trump ended up spending the night in the Hoosier state because his plane had some mechanical issues.
Gingrich, 73, is something of a rabble-rouser who has spent decades in Washington.
So, too, has Christie. Christie as New Jersey governor was part of a scandal that shut down a major bridge into NY, and Gingrich had an affair with a junior staffer while he was in the House of Representatives.