David Jackson

USA TODAY

Donald Trump tapped Indiana Gov. Mike Pence as his running mate on Friday, picking a political partner who has executive and congressional experience as well as support within the GOP's conservative base.

"I am pleased to announce that I have chosen Governor Mike Pence as my Vice Presidential running mate," Trump tweeted, confirming what had been widely reported as likely the previous day. Trump added that a news conference would be held Saturday.

A formal announcement of his running mate had been scheduled for Friday in New York, but Trump postponed it Thursday following the terrorist attack in Nice, France.

Pence didn't even endorse Trump ahead of Indiana's Republican primary on May 3 — the governor went with Texas Sen. Ted Cruz, a strong social conservative — but quickly switched to the New York businessman after his big win in the Hoosier State all but nailed down the Republican presidential nomination.

"My family and I couldn't be more happy for the opportunity to run with and serve with the next president of the United States," Pence told reporters after Trump's announcement.

Pence also tweeted, saying he was "honored" to join Trump on the ticket and to help "make America great again," invoking the real estate mogul's campaign slogan.

The Trump campaign also released a video of the real estate mogul and Pence previously on the campaign stump together shortly after the announcement of the GOP ticket.

Throughout the running mate selection process, Trump and aides said they wanted someone with political experience who could help get bills through Congress. They also wanted someone who has good relations with party conservatives who don't particularly like the nominee, seeing the vice presidential selection as a bid for party unity.

Trump has also said he likes Pence personally and believes he is a winner.

Republicans praise Pence as Trump running mate

The campaign of Democratic opponent Hillary Clinton served notice it would attack Pence's conservative record, saying he favors policies that hurt minorities and favor the wealthy and powerful — people like Trump.

“By picking Mike Pence as his running mate, Donald Trump has doubled down on some of his most disturbing beliefs by choosing an incredibly divisive and unpopular running mate," said John Podesta, Clinton's campaign chairman.

Clinton campaign: Pence 'most extreme' VP pick in generation

Democrats also pointed out that Pence disagrees with Trump on issues like trade, including the proposed Trans-Pacific Partnership (TPP) with Pacific Rim nations.

Asked if he had any comment on Trump’s new running mate, White House press secretary Josh Earnest quipped, “You mean the TPP-supporting, Medicaid-expanding Mike Pence? No I don't have any comment on that.”

Pence, who served a dozen years in the U.S. House before winning election as Indiana governor in 2012, is particularly popular with religious conservatives and spent much of his career opposing increased government spending and immigration "amnesty."

By joining Trump's ticket, Pence gives up his re-election bid. Indiana law prohibits a candidate from running in more than one race. Trump aides believe Pence can help lock down a state that is essential to any Republican candidate, and perhaps help in other states like Ohio and Pennsylvania.

The presumptive Republican presidential nominee met with Pence and his wife, Karen, on July 2 at the candidate's golf resort in New Jersey. He later described the governor as "a great guy." Trump and his children also met with Pence at his Indiana home earlier this week.

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In his search for a running mate, Trump also considered former House speaker Newt Gingrich, Alabama Sen. Jeff Sessions and New Jersey Gov. Chris Christie.

Gingrich told a CNN reporter Thursday that he thought Trump would go with Pence, citing his relative youth among other factors.

Pence's popularity with religious conservatives also makes him a target of Democratic opponents, some of whom believe he could have been defeated in the governor's race.

Even before the official announcement, Democrats denounced the Indiana governor for pushing legislation to restrict abortion and gay rights. They also noted that the former blogger and talk show host has questioned whether smoking causes cancer.

Pence is an "anti-gay, anti-choice social warrior with few discernible accomplishments," said Democratic strategist Lis Smith.

Pence was born and raised in the central Indiana town of Columbus. He was first elected to his House seat in 2000, following two unsuccessful runs in 1988 and 1990. In the intervening years, Pence ran a conservative think tank and hosted conservative radio and television talk shows.

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Despite backing from the right, Pence lost overwhelmingly in his bid to become House GOP leader against John Boehner following the 2006 midterm elections.

Pence had been mentioned as a possible Republican presidential contender in recent election cycles but has never sought national office.

The Pence selection ends a months-long search.

Other potential running mates — including former opponents Marco Rubio and John Kasich — expressed no interest in joining Trump's ticket.

As word of Pence's possible selection spread in recent days, Republicans who have been known to criticize Trump said they would welcome the Hoosier State governor.

"It’s no secret I’m a big fan of Mike Pence’s," said House Speaker Paul Ryan, R-Wis. "We’re very good friends, I have very high regard for him. I hope that (Trump) he picks a good movement conservative. Clearly, Mike is one of those."

Contributing: Cooper Allen and Gregory Korte