Then one of her aides tossed her a phone.
Booming from the speaker were loud cheers coming from her campaign headquarters in Brooklyn. It was at that moment, according to an aide who was with her, that it all sank in.
"I love you all!" Clinton exclaimed, as she made her way to a debate watch party for her supporters at the Wynn hotel. "I’ll talk to you later! I love you!"
And for the rest of the week, as she traveled from Nevada to Texas to New Hampshire to Alabama, Clinton has seemed like a new woman. Not only did her well-reviewed debate performance shut down many of her doubters, but the Democratic presidential candidate also seems to have gotten her groove back.
Perhaps it is a winner’s high, but the woman who has been plagued for months by headlines about an e-mail scandal and her main opponent's rising poll numbers, now seems invigorated and refreshed -- smiling, cracking jokes, and loving the rope-line.
At the end of her rally in San Antonio on Thursday, Clinton made her usual rounds glad-handing and taking selfies with supporters. But at the moment the Secret Service appeared ready to usher her out a side exit, Clinton instead was ready for one more round, returning to the rope line to meet with a new crowd that had formed.
Over the past three days, the campaign hosted two large rallies: One in Las Vegas that opened with performances by a mariachi band and Mexican dancers. And another in San Antonio where her team switched up Clinton’s usual campaign playlist and blasted Selena.
In Texas, where she received the endorsement of U.S. Housing Secretary Julian Castro (a potential running mate if Clinton wins the nomination), the audience chanted "Hillary! Hillary!" several times during her remarks.
Clinton’s aides are clearly soaking it all in and, at the same time, looking for ways to leverage the moment.
As they gathered near the casino of the Wynn hotel in Las Vegas for a late-night, celebratory dinner after the debate, one aide observed, "it feels like opposite day," citing a Politico headline that read "Clinton Crushes It."
The campaign also believes the debate revealed one of Sanders' weak spots: Gun control -- one of the only issues where Clinton stands to the left of her Democratic rival. It was no accident that gun control was the topic of two of her campaign events this week at which she took subtle swipes at Sanders for his comment during the debate that "all the shouting in the world" will not keep guns out of the wrong hands.
But for a few days, at least, Clinton seems to have found her footing.
When asked by a reporter as she worked the crowd in San Antonio if she was having a good day, Clinton simply smiled and gave one big, hearty thumbs up.