Here's a look at some of the at-times controversial candidate's most memorable quotes from this year.
"Because a lot of people who go into prison go into prison straight -- and when they come out, they're gay. So, did something happen while they were in there? Ask yourself that question."
--March 4, 2015, on CNN. Carson was saying being gay is a choice, but he later backtracked, saying his "choice of language does not reflect fully my heart on gay issues."
"I would not advocate that we put a Muslim in charge of this nation. I absolutely would not agree with that."
--Sept. 20, 2015, on "Meet the Press." He later clarified he would support a Muslim who rejects the tenets of Sharia law.
"I don't know."
--Sept. 30, 2015, in New Hampshire when asked how he would handle a then-approaching Hurricane Joaquin as president.
"If people don't speak up for what they believe, then other people will change things without them having a voice. Hitler changed things there and nobody protested. Nobody provided any opposition to him."
--Sept. 30, 2015, in New Hampshire. Carson said he was not comparing President Barack Obama to Hitler.
"The number-one cause of death for black people is abortion."
--Aug. 13, 2015, on Fox News.
"You look at some of these caves and things out there one drone strike, boom, and they're gone."
--Aug. 19, 2015, near the Mexican border on border security. He later clarified he was only talking about the caves and not using lethal force.
"I think the likelihood of Hitler being able to accomplish his goals would have been greatly diminished if the people had been armed."
--Oct. 8, 2015, on CNN regarding the school shooting in Oregon. He clarified that he was saying "when tyranny occurs traditionally around the world, they try and disarm the people first."
"Not only would I probably not cooperate with him, I would not just stand there and let him shoot me. I would say, 'Hey guys, everybody attack him! He may shoot me but he can't get us all.'"
--Oct. 6, 2015, on Fox News about what he would have done in the Oregon shooting situation.
"There is no doubt that this senseless violence is breathtaking -- but I never saw a body with bullet holes that was more devastating than taking the right to arm ourselves away."
--Oct. 5, 2015, on Facebook regarding gun control.
"I have had a gun held on me when I was in a Popeye's organization (in Baltimore). ... Guy comes in, put the gun in my ribs. And I just said, 'I believe that you want the guy behind the counter.'"
--Oct. 7, 2015, on Sirius XM on the controversy over his Oregon shooting comments.
"As a teenager, I would go after people with rocks, and bricks, and baseball bats, and hammers. And, of course, many people know the story when I was 14 and I tried to stab someone."
--Oct. 25, 2015, on "Meet the Press," making the point he hasn't always been so soft-spoken.
"Think about this. During slavery -- and I know that's one of those words you're not supposed to say, but I'm saying it -- during slavery, a lot of the slave owners thought that they had the right to do whatever they wanted to that slave. Anything that they chose to do."
--Oct. 25, 2015, on "Meet the Press" on opposing abortion in all instances.
"If you're gonna have rules for war, you should just have a rule that says no war. ... Other than that, we have to win. Our life depends on it."
--Feb. 16, 2015, on Fox News regarding limited military oversight.
"Like most psychopaths. That's why they're successful. That's the way they look. They all look great."
--Jan. 20, 2015, while watching Obama deliver his State of the Union address, as quoted by GQ.
"We've got ISIS. They've got the wrong philosophy, but they're willing to die for what they believe while we are busily giving away every belief and every value for the sake of political correctness."
--Jan. 15, 2015, at the RNC's Winter Meeting. He later added the "liberal media" would take the comments out of context.
"I haven't said anything about how I'm the first one to do something, so let me do that. I'm the only one to separate Siamese twins ... the only one to take out half of a brain, though you would think that if you go to Washington that someone had beat me to it."
--Aug. 6, 2015, during the first Republican GOP debate.
"I want people to see me as an honest person, a person who is actually willing to express what they believe. ... The way I look at it, if people don't like that, I'd rather not be in office. I don't want to be in office under false pretenses, just saying things people want to hear so I can get elected."
-- Oct. 12, 2015, in an interview with The Hill.
