It was a case study in how a single remark can shake up a campaign before a speech is even over.
The cameras were rolling in Wilmington, N.C., as Republican nominee Donald Trump told his audience about how his Democratic opponent, Hillary Clinton, would clamp down on gun rights.
"Hillary wants to abolish, essentially abolish, the 2nd Amendment," Trump said Tuesday afternoon, apparently reading from notes on his lectern. Then he looked up to freestyle with his audience. "By the way, and if she gets to pick" — here, Trump paused as the crowd booed — "if she gets to pick her judges, nothing you can do, folks."
He added: "Although the 2nd Amendment people -- maybe there is. I don't know."
Trump did not elaborate, and in the auditorium, the crowd did not seem to respond strongly. Some listeners clapped, one gaped, someone whistled.
Online, political chaos erupted.
ABC News campaign reporter Candace Smith, who was attending the rally, tweeted Trump's remark at 3:06 p.m. Eastern time — and her tweet got retweeted more than 2,500 times. Eddie Vale, the vice president of the liberal super PAC American Bridge, tweeted at the same time: "ummmmm Trump just alluded to people shooting Clinton."
"Hard to say if it's a joke from delivery," Vox's Zack Beauchamp tweeted a few minutes later. "But to a certain extent, it doesn't matter."
For the next half an hour, video of Trump's remarks spread online, earning thousands of retweets. One user tweeted a short video of an older man sitting behind Trump who was agape at the remark, adding, "Guy behind Trump immediately realized what he said was a problem." The video got more than 4,000 retweets.
The Guardian sent a news alert: "Donald Trump hints at assassination of Hillary Clinton by 'second amendment people.' "
Democratic Sen. Christopher S. Murphy of Connecticut, a gun-control advocate, tweeted a link to federal law, and said, "Casual reading assignment tonight: federal criminal statute on threatening to kill a candidate for President."
"Was @realDonaldTrump suggesting his supporters shoot Hillary? Shoot her nominee? Who knows. It's all so disgusting and embarrassing and sad," Murphy added in another tweet.
Clinton campaign manager Robby Mook then joined in with his own statement: "This is simple — what Trump is saying is dangerous. A person seeking to be the President of the United States should not suggest violence in any way."
About an hour after Trump's remark — long after the horse had galloped out of the barn — his campaign issued its own response to the outrage. The statement said Trump was referring to gun advocates' "political power."
"It's called the power of unification — 2nd Amendment people have amazing spirit and are tremendously unified, which gives them great political power," Trump spokesman Jason Miller said in the statement. "And this year, they will be voting in record numbers, and it won't be for Hillary Clinton, it will be for Donald Trump."
Soon after, the National Rifle Assn. came to Trump's defense, and the powerful lobbying group interpreted Trump's remark as calling for something other than armed insurrection.
"@RealDonaldTrump is right. If @HillaryClinton gets to pick her anti-#2A #SCOTUS judges, there's nothing we can do. #NeverHillary," the NRA tweeted from its official account. It added in a second tweet: "But there IS something we will do on #ElectionDay: Show up and vote for the #2A! #DefendtheSecond #NeverHillary"
Trump soon went on Fox News and agreed with host Sean Hannity that he had been talking about voters, not violence. "Nobody in that room thought anything other than what you just said," Trump said. "This is a political movement. ... And there can be no other interpretation."
There was still one more key voice to be added to the conversation — that of the agency responsible for investigating threats to presidential candidates.
"The Secret Service is aware of the comments made earlier this afternoon," the U.S. Secret Service tweeted from its official account — saying nothing further.
The Secret Service would have been immediately aware of Trump's remarks, of course. Its agents were there, part of their mission to keep watch over Trump.