For the first time since the first televised debate between John F. Kennedy and Richard Nixon in 1960, there will be no live audience at CNN's studio in Atlanta.

The candidates' microphones will be muted unless it is their turn to speak. They will have two minutes to respond to questions and one minute for rebuttals, and there will be a red flashing light to indicate to them their time is about to expire.

The 90-minute program will have two commercial breaks, but Trump and Biden won’t be able to consult with their teams during them. No props or note cards are allowed on stage.

Here's what experts said about the new rules, and how they may help or hurt each candidate.

Several possible vice presidential picks for Trump are in Atlanta for the debate.

Sens. Marco Rubio, R-Fla., Tim Scott, R-S.C., and J.D. Vance, R-Ohio, Rep. Elise Stefanik, R-N.Y., and former Housing and Urban Development Secretary Ben Carson were seen in a picture posted to X by Stefanik.

Trump has repeatedly teased an announcement of who will join him in the 2024 ticket, but he has yet to make a final decision.

Voters across Wisconsin, Michigan, Georgia and Pennsylvania spoke with ABC News about their unhappiness with both candidates and what they're looking to hear from them during the debate.

"I'd like to see what they're going to do for small businesses in this country," said Scranton resident Jennifer Merceau, whose husband owns a masonry company.

Janee Johnson, who works at Toast 'N Jams in Muskegon, Michigan, said the focus should be on doing the "right things for America."

Michael Kordecki, the owner of that restaurant, wishes he could tell the candidates to "be more positive about America, about our future, and about what we can do with or without new people coming into the country."

Read more about these voters here.

With 131 days until Election Day, this faceoff is occurring months ahead of the usual fall timeline.

"The combination of having so many people with doubts about both candidates, coupled with the first debate occurring before either convention, heightens its potential importance," Republican political strategist Whit Ayres told ABC News.

Veteran Democratic strategist James Carville told ABC News: "People's attitudes are very fixed and voters tend to be pretty entrenched. The person that 'wins' ... in this debate is going to be the one that provides voters with some new information."

-ABC News' Isabella Murray and Tommy Barone

Biden had a poor start to this debate, and if he ends up being viewed as the "loser" tonight, he'd be just the latest incumbent president to go through this. Incumbent presidents like Ronald Reagan in 1984, George W. Bush in 2004, Barack Obama in 2012 and Trump in 2020 all lost 2 to 3 points in the polls after their first debate.

Reagan, the last president to face real questions about his age -- he was 73 in 1984 -- had a meandering performance that prompted questions about whether he had gotten too old for the job. Reagan shot back in the second debate against Democratic nominee Walter Mondale, who was in his mid-50s, with the famous line: "I will not make age an issue of this campaign. I am not going to exploit, for political purposes, my opponent's youth and inexperience." Reagan, however, also had a roaring economy, which helped him win a landslide reelection victory.

-Geoffrey Skelley, 538