Republicans Pile On Donald Trump At Reagan Library Debate

A big night in Campaign 2016.

Eleven leading Republican presidential candidates went head to head in a political showdown during their second primetime debate.

Frontrunner Donald Trump touched on immigration reform, the Iran Nuclear Deal and relations with Russia. Meanwhile, Carly Fiorina called on republicans to submit a budget defunding planned parenthood, despite a veto threat.

11:10 p.m. Another lighthearted question for the candidates: What would your Secret Service code name be?

• Christie: "I've been called a lot of names by a lot of different people...I would just say true heart."
• Kasich: "My detail, they called me Unit One."
• Fiorina: "Secretariat"
• Walker: "Harley"
• Bush: "Eveready - it's high energy, Donald" (a nod to Trump's insult that he's low energy)
• Trump: "Humble"
• Carson: "One nation"
• Cruz: "Cohiba" (a Cuban cigar brand)
• Rubio: "Gator"
• Huckabee: "Duck hunter"
• Paul: "Justice never sleeps"

11:04 p.m. A lighthearted question for the candidates: In light of the fact that the Treasury Department plans to put a woman on the $10 bill, who would the candidates put there?

• Paul: "I think Susan B. Anthony might be a good choice."
• Huckabee: "That's an easy one I'd put my wife on there."
• Rubio: "Rosa Parks."
• Cruz; "I wouldn't change the $10 bill, I'd change the $20...I'd leave Alexander Hamilton right where he is...I very much agree with Marco that it should be Rosa Parks."
• Carson: "I'd put my mother on there."
• Trump: "I think my daughter Ivanka...other than that we'll go with Rosa Parks."
• Bush: "I would go with Ronald Reagan's partner, Margaret Thatcher."
• Walker: "I'd put Clara Barton. I once worked for the American Red Cross."
• Fiorina: "I wouldn't change the $10 bill or the $20 bill, I think honestly it's a gesture, I don't think it helps to change our history. What I would think is that we ought to recognize that women are not a special interest group, women are the majority of this nation, we are half the potential of this nation and this nation will be better off when every woman has the opportunity to live the life she choses."
• Kasich: "It's probably not maybe legal but I would pick Mother Theresa."
• Christie: "I think the Adams family has been shorted in the currency business, our country wouldn't be here without John Adams and he wouldn't be able to do it without Abigail Adams."

10:50 p.m. Tapper brings up the fact that Trump has linked vaccines to autism and asks Carson, a pediatric neurosurgeon, to weigh in on whether he should stop saying that.

"There have been numerous studies and they have not demonstrated that there's any correlation between vaccinations and autism. This is something that was spread widely 15 or 20 years ago and it has not been adequately revealed to the public what's actually going on," he said. But, he said, there are some vaccinations which don't prevent diseases that would kill people and said there should probably be some discretion. He blamed the concerns about vaccines on the fact that they are supported by "big government."

As to whether Trump should stop making the link, he said he can read more and will make an intelligent decision.

Trump said, "I am totally in favor of vaccines" but said they should be spaced farther apart and given in smaller doses. He cited the case of an employee whose child got vaccines and then two weeks later got a fever and then autism.

Asked to respond, Carson said, "He's an okay doctor," -- a riff on the criticism that Trump fired his way.

"The fact of the matter is we have extremely well-documented proof that there's no autism associated with vaccinations but it is true that we are probably giving way too many in way too short period of time," he said, saying he would support cutting down on the number and frequency of vaccinations.

Paul, the other doctor on stage, was also asked to respond.

"I'm all for vaccines but I'm also for freedom. I'm also a little concerned about how they're all bunched up," he said.

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