If I was advising Trump, I would tell him to say or do something incredibly controversial ASAP to suck all the attention from Fiorina et al
— Dan Pfeiffer (@danpfeiffer) September 17, 2015
I didn't see the tweet at the time, but that was my first thought when I learned about the incident -- that the questioner was a plant.
"We have a problem in this country. It's called Muslims," an unidentified man who spoke at a question-and-answer town hall event in Rochester, New Hampshire asked the mogul at a rally Thursday night. "You know our current president is one. You know he's not even an American."But I watched the clip, and the exchange seemed too spontaneous, and not crafted for maximum impact (I'd have expected Trump to be more pointed about in his response to the questioner calling Obama a Muslim if he were trolling for did-he-really-say-that? media coverage, and I also would have expected a more pointed response to the training camp question.)
A seemingly bewildered Trump interrupted the man, chuckling, "We need this question. This is the first question."
"Anyway, we have training camps growing where they want to kill us," the man, wearing a "Trump" T-shirt, continued. "That's my question: When can we get rid of them?"
"We're going to be looking at a lot of different things," Trump replied. "You know, a lot of people are saying that and a lot of people are saying that bad things are happening. We're going to be looking at that and many other things."
The real estate mogul did not correct the questioner about his claims about Obama before moving on to another audience member.
In any case, it does seem as if Trump needed help regaining control of the news cycle, which Carly Fiorina has owned since the debate, and this exchange helped him accomplish that. However, Trump doesn't seem to have needed help with actual GOP voters, if this Morning Consult poll is correct:
Poll: Fiorina Wins Debate, Trump Still Leads
... A plurality of 29 percent of registered voters who watched the debate said Fiorina won, just higher than the 24 percent who said real estate mogul Donald Trump came out on top....
Trump continues to lead the Republican primary field. Thirty-six percent of registered voters who watched the debate said they would choose Trump, compared with 12 percent for Carson and 10 percent for Fiorina. Rubio placed fourth, at 9 percent, followed by 7 percent for Sen. Ted Cruz (R-Texas) and 6 percent for Bush and New Jersey Gov. Chris Christie (R).

So poll-watching GOP voters say Fiorina won the debate -- but that she barely beat Trump, even though, according to conventional wisdom, he had a mediocre-to-terrible night. And Trump's numbers have gone up with debate-watching Republican voters, as the chart shows. Apparently Fiorina is taking votes from other candidates -- Carson, Bush, Paul (Paul now seems to be close to Bobby Jindal territory). Neither she nor the other gainers (Rubio, Christie, Kasich, Cruz) took any votes from Trump.
Ed Kilgore writes:
So Carly’s boom really just means that now 58% of respondents support a candidate with zero experience in public office. And that’s among the people who actually watched the supposedly Trump-destroying debate.Yup.
We’ll see what later polls say, but for the present the idea things are about to return to normal and voters will sagely choose between “real candidates” Bush and Rubio and Kasich looks no closer to reality than before.