Tony Cook, James Briggs, and Chelsea Schneider

IndyStar

Update, 11 a.m Friday: Donald Trump acknowledged via Twitter on Friday what the IndyStar confirmed Thursday: Indiana Gov. Mike Pence will be his running mate.

Earlier story:

Gov. Mike Pence is dropping his re-election bid in Indiana to become Donald Trump’s running mate.

IndyStar confirmed shortly after noon Thursday that Trump is planning to announce Pence as his selection for vice president. Several national news outlets, including CNN and ABC News, later reported Trump had offered the post to Pence and he had accepted, ending a weekslong casting call during which Trump vetted a handful of high-profile Republicans.

Trump had been scheduled to formally announce his pick at a news conference in Manhattan at 11 a.m. Friday, but delayed the event in the wake of an attack in Nice, France, that left more than 70 people dead.

The delay could leave Pence, who had already traveled to New York, in political limbo. He faces a noon Friday deadline to withdraw from the governor's race to allow Indiana Republican leaders to select a replacement candidate.

The developments capped another wild day in the vice presidential search, with Trump's campaign team insisting throughout the day that no decision had been made, even as Pence was being whisked toward Manhattan in a motorcade after flying on a private plane from Indianapolis to Teterboro, N.J.

In a Thursday evening interview with Fox News, Trump said he still hadn't made a "final, final" decision. It wasn't clear if those comments were meant to maintain a sense of surprise for the planned announcement, but Republican strategists, including a former Trump adviser, have repeatedly emphasized Trump's unpredictability and noted anything is possible.

Trump's long-awaited decision upends the political landscape in Indiana and at least partially remakes the Trump campaign.

Trump's VP? 10 things to know about Indiana Gov. Mike Pence

In Pence, Trump adds a social conservative whom GOP strategists say will reassure rank-and-file Republicans that Trump can be trusted to pursue their interests. Veteran political observers say Pence, a former U.S. House member and chairman of the House Republican Conference, will provide a disciplined counter to Trump’s improvisational campaign style. Pence also brings fundraising power and credibility on a wide range of policy issues that are important to conservatives.

Pence would officially become the vice presidential nominee during the Republican National Convention, which starts July 18 in Cleveland. He could become the first vice president from Indiana since Dan Quayle took office in 1989 under George H.W. Bush.

Pence’s departure for national politics sets up a scramble among Indiana Republicans to determine who will replace Pence to run against Democratic challenger John Gregg in the November gubernatorial election.

For the first time in state history, the Indiana Republican State Committee will determine the GOP candidate for governor in a process that could last into August. The 22-member panel has 30 days to choose Pence’s replacement on the ballot. Once it’s clear who will be vying for the Republican nomination, the committee must provide a 10-day notice before it votes. That means, at the earliest, the process will conclude in late July.

Lt. Gov. Eric Holcomb, who has not yet publicly said he will seek the office, is thought to be a front-runner. U.S. Rep. Susan Brooks of Carmel plans to withdraw from her congressional race and run for governor, said Murray Clark, a former state Republican Party chairman and a partner at the law firm Faegre Baker Daniels. U.S. Rep. Todd Rokita has said he plans to run.

First, though, Pence must file paperwork to withdraw his name from the ballot. While the deadline to do that is noon Friday, Pence could withdraw, then ask the state's GOP central committee to renominate him if he doesn't get the vice presidential nomination.

Pence's elevation in the political world comes as he faced a tight race in Indiana. The most recent public poll, which was conducted in May, showed Pence leading Gregg 40 percent to 36 percent, a virtual tie when factoring in the 4 percent margin of error. Pence defeated Gregg in the 2012 race by 3 percentage points.

Pence, a vocal Trump supporter since he clinched the Republican nomination, will turn his attention toward helping the real estate mogul defeat Democrat Hillary Clinton in November. Even without Pence, Trump has been closing the gap. A national CBS News/New York Times poll released this week shows Clinton and Trump tied at 40 percent just one month after Clinton had a 6 percentage point lead. Yet, projections based on state polls suggest Clinton has an advantage, albeit a diminishing one.

Trump appeared to have winnowed the field of potential running mates from about 10 people last week in a fashion that some have compared to a reality-TV show, complete with auditionlike campaign appearances. Aside from Pence, the other favorites were former House Speaker Newt Gingrich and New Jersey Gov. Chris Christie.

Pence essentially tried out for the position during a Trump rally in Westfield and a fundraiser in Indianapolis on Tuesday. Pence, who has traditionally eschewed negative campaigning, used the rally to attack Clinton for the loss of U.S. personnel in Benghazi, Libya, and compare Trump to Ronald Reagan.

3 times Gov. Mike Pence distanced himself from Donald Trump

Speculation that Trump would pick Pence intensified after Trump and his family unexpectedly dined with Pence and his wife at a swanky Downtown restaurant Tuesday night, then had breakfast at the governor's residence the next morning.

Call IndyStar reporter Tony Cook at (317) 444-6081. Follow him on Twitter:@indystartony.

Call IndyStar reporter James Briggs at (317) 444-6307. Follow him on Twitter: @JamesEBriggs.

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