Americans need to know that there are "two Donald Trumps," Carson said.
One is the man who has dominated headlines and the Republican primary with his brash statements, said Carson, a retired neurosurgeon who captivated some conservative voters with his unconventional presidential campaign before dropping out of the race last week.
The other is "very cerebral and sits there and considers things very carefully."
"He's much more cerebral and a much more reasonable person than comes across," Carson said of Trump. As voters "begin to see the real individual there," he said, "I think we’re going to be comforted as a nation."
The pair appeared together at a news conference at Trump's Mar-a-Lago Club in Palm Beach, Fla., a day after Trump appeared in a surprisingly civil debate -- "elegant," in Trump parlance -- alongside his three remaining competitors for the Republican nomination.
Echoing a plea Trump has made himself in recent days, Carson implored GOP leaders to coalesce around the controversial front-runner.
"A house divided against itself cannot stand," Carson said, echoing the biblical reference once cited by Abraham Lincoln, in allusion to some Republican leaders who have said they will not back Trump.
"I want the will of the people to be heard," Carson said. "I want the political process to play out as it should play out."
While Trump and Carson clashed at times on the campaign trail, they embrace many of the same political beliefs. Both have called for dramatic measures to reduce the number of immigrants living illegally in the U.S., and both have made controversial statements about Muslims. Last fall, Carson said that in order for a Muslim to become president, "you have to reject the tenets of Islam."
A member of the Seventh-day Adventist Church who frequently drops biblical references, Carson's endorsement could help boost Trump’s support among evangelical Christian voters, many of whom flocked to Carson's outsider campaign, while hurting Trump rival Ted Cruz, who counts evangelicals as part of his base.
Carson has had a rocky relationship with Cruz after accusing the Texas senator of dirty tricks to dissuade voters from backing Carson on the night of the Iowa caucuses.
This week, Cruz won the endorsement of another Republican candidate who dropped out of the race, former Hewlett-Packard Chief Executive Carly Fiorina.
Another onetime candidate, former Florida Gov. Jeb Bush, is said to be meeting with Trump’s rivals, although it is unclear whether Bush will endorse anyone ahead of Florida's primary on Tuesday.
Carson said he made his endorsement decision after praying about it, and after a friend called and said: “I had a dream about you and Donald Trump."
"I got a lot of indications," said Carson, a political novice whose sometimes oddball statements made him a frequent target of jokes on the campaign trail. Appearing on "Saturday Night Live" last year, Trump joked that "Carson is a complete and total loser."
Carson and Trump blamed their earlier friction on the nature of politics, with Carson saying he was not personally offended. “We move on because it’s not about me, it’s not about Mr. Trump," he said.
For his part, Trump praised Carson as “a special, special person" who has led "an awe-inspiring life." Trump said he and Carson had a good discussion on education this week, and said he hopes to keep Carson involved in his campaign and potential presidency.
Keeping in line with his recent shift away from the insults and name-calling that have characterized much of his campaign, Trump refrained from criticizing his competition for the Republican nomination. And he wanted to be sure that others noticed. Speaking of Thursday's debate, Trump said, "There were a lot of good feelings in that room. And I think frankly it was something that the Republican Party needed."
He urged Republican leaders to embrace his campaign.
"The Republican Party should grab this," he said, bragging that he has the potential to win Rust Belt states for Republicans in the November general election.
"I will get states that are unbelievable for the Republican Party, that are unthinkable for the Republican Party," he said.
Follow me on Twitter: @katelinthicum
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