The Note: Another Trump Firestorm

— -- Notables

--TRUMP LETS COMMENT ABOUT MUSLIMS BEING 'PROBLEM' IN US SLIDE. GOP frontrunner Donald Trump let an audience member slide at a New Hampshire town hall after the man said Muslims were a "problem in this country" and that the president was not an American. During a question and answer session in Rochester, New Hampshire, a gentleman stood and said, "We have a problem in this country, it's called Muslims. We know our current president is one, you know he's not even an American." "We need this question," Trump said before chuckling. The man went on to ask Trump explicitly: "But anyway, we have training camps brewing where they want to kill us. That's my question, when can we get rid of it?" Trump, who is leading in Republican polls, did not address the comment about the President and said simply, "We're going to be looking into a lot of different things." ABC's MARYALICE PARKS reports: http://abcn.ws/1KkgAkX

--TRUMP'S RESPONSE. After the event, Trump's campaign told ABC News that he had difficulty understanding the question and was referring to mention of training camps. Asked if Trump believed there were camps in the U.S., the campaign said, "Yes." The campaign also said the comments about Muslims in America were the opinions of one man in the crowd. "The media wants to make this issue about [President] Obama. The bigger issue is that Obama is waging a war against Christians in this country," the campaign said in a statement. "Christians need support in this country. Their religious liberty is at stake." http://abcn.ws/1KkgAkX

--SANDERS REACTS. @BernieSanders: Trump must apologize to the president and American people for continuing the lie that the president is not an American and not a Christian.

--ANALYSIS--ABC's RICK KLEIN: Everyone is feeling the Bern now - even Hillary Clinton, and she's putting it on the White House. Jeb Bush has added Bernie Sanders to the stump, in a way similar to how Clinton uses Donald Trump: "Hillary's kind of drafting right behind Bernie," Bush said in Nevada. Also Thursday came news that the Sanders campaign detonated a $1.2 million money bomb based on a ham-handed attempt by the super PAC supporting Clinton, Correct the Record, to link Sanders to Hugo Chavez. As for Clinton herself, the anger she flashed at the White House over the delay in a final decision on the Keystone Pipeline makes a whole lot more sense in the context of Sanders' fierce opposition. "I can't wait too much longer," Clinton said. "I am putting the White House on notice. I am going to tell you what I think soon." That's hardly an explosive revelation, but it's a difficult one to imagine without Sanders in this race. To take that one step further, if Sanders committed to additional debates, could Clinton refuse?

TODAY ON THE TRAIL with ABC's SHUSHANNAH WALSHE: The story of the day is still the firestorm around Donald Trump and a questioner last night at a town hall in New Hampshire. Expect this to continue to dominate the conversation today. He's in South Carolina where he will be speaking at the Take Back America conference in Greenville. Jeb Bush, Scott Walker, Ben Carson, Ted Cruz, Rick Santorum, Marco Rubio, Carly Fiorina, Bobby Jindal, and Chris Christie are all speaking at the conservative conference sponsored by Heritage Action this afternoon and evening. Bush will also speak at the Republican Leadership conference on Mackinac Island in Michigan this evening. Walker, Carson and Santorum all have other events while in South Carolina. Walker has an event in Spartanburg this morning and Carson is speaking this morning at a healthcare summit, also in Greenville. Santorum will be at the Columbia Greek Festival, also this morning. The only candidate in Iowa today is Lindsay Graham who has five events in the Des Moines area. Mike Huckabee is in California with stops in Anaheim.

Hillary Clinton is in both New Hampshire and Maine. She holds morning and evening events in the Granite State and an afternoon "grassroots organizing" meeting in Portland, Maine. It's Bernie Sanders's chance to get the Colbert Treatment. He'll be on the Late Show tonight. Chelsea Clinton continues her book tour with a homecoming of sorts, she will stop in Little Rock.

THIS WEEK ON "THIS WEEK": GOP presidential candidate, Florida Sen. Marco Rubio, comes to "This Week" following the second Republican presidential debate. Plus, New York City's Mayor Bill de Blasio discusses the Pope's upcoming trip to the U.S. and the race for the Democratic nomination for president. Then, the Powerhouse Roundtable debates the week in politics, with ABC News contributor Matthew Dowd, ABC News contributor and Republican strategist Ana Navarro, ABC News' Cokie Roberts, and Democratic strategist and ABC News contributor Donna Brazile. See the whole political picture, Sunday on "This Week."

THE BUZZ

with ABC's PAOLA CHAVEZ and VERONICA STRACQUALURSI

7 WAYS THE SECOND REPUBLICAN DEBATE CHANGED THE 2016 PRESIDENTIAL RACE. When 23 million people have their eyes on the television, the stakes are high. The Republican presidential candidates were offered yet another major opportunity in the road to the White House Wednesday night, a chance to jockey for a place in the spotlight and shake up the field. We've seen debates tank the bids of some candidates -- like Rick Perry's "oops" moment four years ago. And we've seen some ignite a spark in the campaigns of candidates like Carly Fiorina a month ago. ABC's RYAN STRUYK looks at how the second Republican debate from Wednesday night could shake up the 2016 field. http://abcn.ws/1Ktc7Oe

BREAKING DOWN THE GOP DEBATE WITH MATTHEW DOWD AND LZ GRANDERSON: WINNERS AND LOSERS. ABC News political analysts Matthew Dowd and LZ Granderson wrapped up Wednesday night's debate discussing the winners --and losers -- of the night and everyone in between. The second round of GOP debates, which featured 11 Republican presidential candidates on the main stage and four others at a gathering of lower-tier contenders, was filled with jaw-dropping moments and some great one-liners. ABC's PAOLA CHAVEZ and MADISON JAROS report a look at some of Dowd and Granderson's top takeaways from the night. http://abcn.ws/1FQ5NL9

HILLARY CLINTON: WHY SHE CONTINUES TO IGNORE BERNIE SANDERS. During a campaign stop in Iowa on Monday, Hillary Clinton was asked twice about Bernie Sanders: Once by a 20-year-old college student who wanted to know Clinton's views on him, and another time by a local reporter who asked if she was "worried" about him as he gains in the polls. In response, Clinton told the student that there will be "plenty of time" to draw contrasts in the future. She told the reporter that no, she's not worried. And she told both of them that she'd like, instead, to focus on the republicans. According to ABC's LIZ KREUTZ, Clinton did all of this, without ever mentioning her democratic challenger's name -- not even once. http://abcn.ws/1KjfqWS

HILLARY CLINTON 'PUTTING THE WHITE HOUSE ON NOTICE' ABOUT KEYSTONE PIPELINE. Hillary Clinton is changing her tune on Keystone (sort-of). The democratic presidential candidate on Thursday expressed frustration over the Obama administration's delay on making a decision on Keystone XL pipeline, and said that she is "putting the White House on notice" and will make her position known "soon" -- something she so far refused to do. "I have been waiting for the administration to make a decision. I thought I owed them that," Clinton said during a town hall at the Concord Boys and Girls Club, when asked by a female voter about the multi-billion dollar pipeline that runs from Canada to the Gulf Coast, ABC's LIZ KREUTZ reports. "I can't wait too much longer. I am putting the White House on notice. I am going to tell you what I think soon." http://abcn.ws/1KpLJjM

GOP DEBATE HUNK'S IDENTITY REVEALED. Mystery solved...sort of. Everyone was dying to know who the hunk was sitting behind CNN moderator Jake Tapper at Wednesday night's GOP debate. He stole the spotlight from the Republican presidential candidates and everyone was asking on Twitter: Is he single? http://abcn.ws/1QkmK6b

OBAMA THANKS 3 AMERICAN HEROS WHO THWARTED TRAIN TERROR ATTACK. President Obama welcomed the three Americans who thwarted a terrorist attack on a passenger train headed to Paris last month to the Oval Office Thursday, crediting their courage and teamwork for pinning down the gunman and saving countless lives. ABC's JOHN PARKINSON reports, the president said he was pleased to have the opportunity to shake the hands of Airman 1st Class Spencer Stone, Specialist Alek Skarlatos and Anthony Sadler. http://abcn.ws/1QJcWDs

WHY SEN. SUSAN COLLINS GOT A RED ROSE ON THE SENATE FLOOR. No, it wasn't the Congressional version of "The Bachelor." ABC's ALI WEINBERG reports, it was to honor the senior Maine senator for casting her 6,000 consecutive vote, a perfect record since she took office in January 1997 -- making her the longest-serving member of the current Senate to have never missed one. http://abcn.ws/1KjGC7T

JEB ADDS BERNIE TO STUMP SPEECH. For the first time, we've heard Jeb Bush now adding Bernie Sanders to his stump speech, signaling a shift in how the campaign views the Democratic field, ABC's CANDACE SMITH notes. "Hillary Clinton and Bernie Sanders, know what their views are. Hillary's kind of drafting right behind Bernie. Bernie Sanders has already promised $18 trillion in new spending programs. It's impossible to imagine," Bush said yesterday in Las Vegas. He mentioned Sanders again when saying that between him, Clinton and "whoever is else is going to run" will just lead to a third term for President Obama. Trump and other Republican candidates were never mentioned by name, though he made a veiled stab at Trump. "I'm not gonna get my foreign policy based on 'watching the shows' or say, don't worry about it, I'll figure it out later."

COLUMN: THE POPE AND THE DONALD: OPPOSITES IN COMMON. What do Pope Francis and Donald Trump have in common and inform us broadly? When old traditional institutions falter, are unresponsive to the public, and begin to be dismantled, the old rules and expectations no longer apply, MATTHEW DOWD writes in his latest column. http://abcn.ws/1NAin7C

WHO'S TWEETING?

@donnabrazile: Once again, when a voter stands up and questions the President's religion or background, #donaldtrump should have confronted it. #coward

@jswatz: The NYT used to offer a brevity award to reporters; this editorial on MI Rep. Gamrat should win. http://s.mlive.com/qR65UGH

@mikiebarb: A little perspective: about 300 million Americans didn't watch the last presidential debate. (22 million or so did).

@HillaryClinton: Donald Trump not denouncing false statements about POTUS & hateful rhetoric about Muslims is disturbing, & just plain wrong. Cut it out. -H

@kairyssdal: I can never run for president. My bladder couldn't take it.