"I think — I pray — he can be disciplined," Tricia McLaughlin, who was a senior advisor to Vivek Ramaswamy's campaign for the 2024 Republican nomination. However, she added the caveat that any discipline could go out the window if Trump feels like Harris and the moderators are ganging up on him.

"If Trump feels like he’s backed into a corner and feels like it’s three on one, that could be a problem," she said.

Tuesday night's debate will be the first televised presidential debate since June, when President Joe Biden faced off with Trump in Atlanta, Georgia. The president's performance was marred by his consistent slurring of words and apparent fatigue, and kicked off a media firestorm that led to him ending his reelection campaign and urging Democrats to instead support Harris. Now, the vice president will get her biggest chance yet to define herself to undecided voters on the debate stage.

“Most voters have a locked-in view of Trump, so it’s not like his performance will radically change views. He just needs to not be overly aggressive and create a permission structure for swing voters fed up with the economy and the border to vote for him,” an unnamed "close ally" of the ex-president told Politico. “The debate is far more consequential for Kamala Harris because voters don’t have a solidified view of her yet.”

During the June debate, Trump noticeably allowed Biden to stumble on his own and largely stuck to an issues-based approach, attacking the Biden administration on the economy, crime and immigration. But with the 59 year-old Harris' emergence as the new Democratic nominee, the former president is now at risk of appearing elderly and addled. In a New York Times column earlier this week, Democratic strategist James Carville suggested Harris may opt to do as Trump did to Biden, and simply let him talk his way into defeat.

“Harris will want to make personality the issue, which is hard for him to resist, but it will be a bad night for him if he falls back on hurling absurd insults at Harris," said California-based Republican consultant Rob Stutzman — who told Politico he would likely be writing in a name on his own ballot.

“She can deliver a set piece in a debate,” he added. “Will he be able to resist taking the bait? Doubt it. He’ll more likely be like a lab rat hitting the cocaine pan instead of the food pan.”

Tuesday night may be the only time Harris and Trump participate in a televised presidential debate in this election. There will be no audience Tuesday night, and candidates are not allowed to have notes or props with them at the lectern. Trump will deliver the final closing statement, and Harris will appear on the right side of viewers' screens.