Hillary Clinton Prepares to Debate Donald Trump Amid His 'Downward Spiral'

— -- For five days straight, Hillary Clinton has been deep in debate prep for her second face-off against Donald Trump.

The Democratic nominee's camp said all topics are on the table for tonight's debate at Washington University in St. Louis -- including a video released Friday of Trump making lewd and derogatory comments about women in 2005.

"There's a lot of interest in what she'll have to say about his comments from 2005," Clinton's communications director Jennifer Palmieri told reporters Sunday on a flight to St. Louis, referring to the "Access Hollywood" tape released by The Washington Post. "And she'll be ready to do that."

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Palmieri explained that it's hard for Clinton's team to predict exactly how Trump will act on the debate stage because it is "unchartered territory" to face an opponent "in the grips of a downward spiral."

The release of the tape has triggered mass outrage among Republican Party leadership, and many -- including Sen. John McCain -- have now rescinded their endorsements of Trump.

Palmieri marveled that Republicans are just now abandoning the New York real estate mogul.

"There was plenty of reason to believe ahead of this 2005 audiotape that he was not qualified to be president," she said, adding that Republicans let Trump "hijack" their party with "very hateful, divisive rhetoric."

"We don’t think Donald Trump is the only person that should be held accountable for that, that these candidates should as well," she explained.

Meanwhile, in response to the tape, Trump has continued to push the storyline about Bill Clinton's past affairs.

Hours before the debate, he even tweeted a video of Juanita Broaddrick -- an Arkansas woman who claimed Bill Clinton assaulted her when he was the state's attorney general. Sources tell ABC News that Trump is likely to bring up Bill Clinton's past indiscretions during the debate.

Hillary Clinton will be prepared for these attacks about her husband, according to Palmieri.

"She's prepared to answer lots of question," Palmieri added.

The former president will be sitting inside the debate hall tonight, along with Chelsea Clinton and her husband, Marc Mezvinsky.