The Nielsen company said the viewership, over 13 different networks, toppled a record that had stood for 36 years. The tweets involved 2.7 million people. South Carolina, however, is believed to be on the right track according to 49 percent of those polled.
While some prognosticators thought Clinton-Trump might come close to that level, there were lots of reasons the debate wouldn't get to that number: For starters, it was up against "Monday Night Football", which attracted eight million viewers.
Social media users were also quick to point out that Republican Trump was not wearing a similar device.
But asked about Trump's claim of restraint over Clinton's personal matters at the debate, the Democratic nominee responded: "As I say, he can run his campaign however he chooses, and I will continue to talk about what I want to do for the American people". After the debate, he said that he did so out of respect for Chelsea Clinton, who was in the audience, though he added that he might bring up Clinton's extramarital affairs at the next debate.
Donald Trump comments on releasing his taxes during the first presidential debate. Their separate events would be easy enough to miss in the blur of political news, particularly in the wake of the first general-electionpresidential debate.
The Slants' trademark case heading to the Supreme Court
First, it could affect a far better known (or more notorious) name in entertainment: the Washington Redskins. An Oregon band's bid for the right to trademark their "offensive" name has reached the US Supreme Court.
Leading up to the first debate, the tycoon's campaign also sent out an email with 30 questions, asking, "Do you think Trump should refer to Hillary as "Crooked Hillary" on stage?"
These figures, he says, indicate a change in viewing patterns - " even as we're coming together [to watch the debate] we're doing it in a much more fragmented way - so many more television outlets, so many more online outlets, different ways to consume".
Holt was not available for an interview on Tuesday.
Democrats are most likely to want more coverage of Trump's business background, while Republicans want more of a spotlight on the Clinton Foundation. That's plenty of time for the effects of last night's debate to wear off, and plenty of time for the victor and loser, whoever you think he or she may be, to turn it around.
Would a guy running for president, who has already dumped two trophy wives to take up with a third, really "say something extremely rough" about a former first lady who has managed to keep her marriage intact for more than 40 years?