Donald Trump's vice presidential pick hasn't seen eye-to-eye with him on key issues animating the Republican's campaign, including free trade and banning Muslims.
Pence, the governor of Indiana, has called for "swift adoption" of the Trans-Pacific Partnership trade pact with Asian countries. "Trade means jobs, but trade also means security," he said in September 2014.
Trump, by contrast, has made opposition to free-trade deals a centerpiece of his campaign, blasting the TPP as "disastrous," "terrible" and "a continuing rape of our country" by special interests.
In December 2015, Pence joined a group of Republican officials in rebuking Trump's controversial proposal to prohibit Muslims from entering the United States, which won the support of a large majority of GOP voters and boosted Trump in the primaries.
"Calls to ban Muslims from entering the U.S. are offensive and unconstitutional," Pence wrote on Twitter at the time. "Our Constitution guarantees the free exercise of religion. The U.S. cannot discriminate on the basis of religion."
Trump and Pence also have subtle but pronounced differences on social issues. Unlike Trump, Pence wants to make abortion illegal even in cases of rape and incest, and co-sponsored a controversial proposal in 2011 to redefine rape cases connected to abortion laws as "forcible rape."
Unlike Trump, Pence has also pushed for a constitutional amendment banning same-sex marriage, an issue the presumptive nominee barely mentions.
Still, Pence's credibility with evangelical Christians — a group that has mixed feelings for Trump — along with his tax-cutting record as governor and anti-spending record as a congressman are key assets he brings to the ticket. Trump's image is shaky with conservatives, with whom Pence has closely associated throughout his 15-year career.
Pence also has a foothold with establishment Republicans, with whom Trump has had a contentious relationship. Senate Republicans rushed to praise the governor as a welcome addition to the ticket.
Though vice presidential picks tend not to be a major factor for voters, many of Trump's supporters embrace Pence's tougher positions on religious freedom and abortion, and the selection could solidify support among Republicans who have doubted their presumptive nominee's conservative bona fides.
Conversely, Pence's support for free trade and opposition to banning Muslim immigrants from entering the U.S. may raise questions for a different contingent of Trump fans.
White House spokesman Josh Earnest tried to poke at Pence's support on the right, telling reporters that Pence "did important work with the administration to expand Medicaid in his state" under the Affordable Care Act.
Trump and Pence also have disagreed on foreign policy.
Pence voted in 2002 to authorize the war in Iraq, which Trump has attacked presumptive Democratic nominee Hillary Clinton for supporting in the Senate.
Trump wasn't even Pence's first choice in the 2016 race. In April, before the Indiana primary, he tepidly endorsed Texas Sen. Ted Cruz.