Yet the big question for President Joe Biden, fairly or not, is whether he can press the case against Trump. Perhaps nothing matters more than the level of energy and strength the Democratic incumbent projects on stage.

Both men have glaring flaws that present their opponent with tremendous opportunity and risk. They will face a huge national audience that will include many people tuning into their 2020 rematch for the first time and who won’t see another debate until September, magnifying each success or mistake.

Biden and Trump will face off Thursday at 9 p.m. for 90 minutes inside a CNN studio in Atlanta. The debate will be aired on CNN and all major networks (ABC, NBC and CBS) and cable companies like FOX.

Here are some key questions we’ll be watching:

Can Biden perform?

Biden’s seeming low bar for success has been created, at least in part, by Trump and his Republican allies, who have relentlessly mocked the Democratic president for apparent stumbles connected to his age for years. Trump’s allies have questioned whether the 81-year-old Biden can even stay awake and stand up for the entire 90 minutes — even as Trump, 78, has had his own flubs in his speeches at rallies. Trump defended himself Saturday about a moment during the Republican primary when he apparently confused former U.N. Ambassador Nikki Haley for former House Speaker Nancy Pelosi. He told a crowd Saturday that liberals had misconstrued what he called a moment of “pure genius.”

Democrats are hopeful that Biden can bring the same energy he did in his State of the Union address earlier in the year. But a face-off on live television against an opponent who delights in verbal combat is very different from a scripted speech before Congress.

Can Trump tone himself down?

Having already locked up his base, Trump has an opportunity with persuadable swing voters and moderates who fueled Biden’s victory four years ago and now express concerns about both candidates.

But to win over the so-called “double haters,” Trump cannot simply lean into the red-meat talking points, personal insults and conspiracy theories that typically dominate his public appearances. Instead of more talk of retribution or lies about the U.S. election system, he’ll need to offer an optimistic vision for the future and a clear contrast with Biden on traditional kitchen-table issues like health care and education.

He was widely panned for his outbursts in the first 2020 debate with Biden, badgering the then-Democratic nominee and repeatedly interrupting him. Their second debate took a milder tone and focused on their sharply different governing visions.

Navigating the criminal records

Trump’s extraordinary legal baggage creates opportunity and risk for both candidates on stage.

Biden’s campaign has signaled an increasing willingness to lean into Trump’s criminal record in recent days. But aside from a few jabs, Biden himself has largely distanced himself from Trump’s prosecutions to avoid the appearance of political interference.

Trump, who has been alleging for years without evidence that Biden is responsible for prosecuting him, won’t make it easy for the president to toe that line.

Recent polling shows that about half of U.S. adults approve of Trump’s New York conviction. And if voters don’t think the specific convictions are troublesome, Trump’s attempt to conceal an alleged affair with a porn actress is hardly bumper sticker material.

Meanwhile, Biden is aware that Trump may go after his son, Hunter, as the then-president did on the debate stage four years ago. Hunter Biden was recently convicted on three felony charges related to the purchase of a gun while allegedly being addicted to drugs. Trump has also raised questions about Hunter Biden’s foreign business dealings when his father was vice president.

Muted mics and moderators

As is often the case, the moderators and the ground rules will likely shape the debate’s outcome. And the ground rules for this debate, the first of two scheduled meetings, are unusual.

It’s worth noting that the candidates are bypassing the traditional structure determined by the Commission on Presidential Debates and instead relying on a set of mutually agreed rules and conditions.

Biden and Trump will debate at a CNN studio in Atlanta with no audience. There will be no opening statements. Each candidate’s microphone will be muted, except when it’s his turn to speak. No props or pre-written notes will be allowed on stage. The candidates will be given only a pen, a pad of paper and a bottle of water.

A coin flip determined that Trump would deliver the final closing statement.

The event will be moderated by CNN’s Dana Bash and Jake Tapper, two well-respected anchors who have not been shy about calling out Trump’s lies and conspiracy theories.

While Bash and Tapper have led critical coverage of Biden at times as well, Biden’s camp is no doubt hoping that they’ll play an active role in rejecting Trump’s potential falsehoods in real time. While Biden’s microphone will be muted when Trump is speaking, for example, the moderators’ mics will not.

Abortion versus immigration

While style sometimes matters more than substance on the debate stage, both candidates have serious policy challenges to navigate.

For Trump, no issue looms larger than abortion. His Supreme Court appointments while president enabled the court to overturn Roe vs. Wade, which triggered an avalanche of abortion restrictions across the nation. Trump has repeatedly said he was proud of his role in overturning Roe. And Biden will be eager to highlight Trump’s role.

Trump, of course, has said he would not support a national abortion ban if reelected. But given his track record on Roe, he may have more work to do if he hopes to convince women he can be trusted on a key health care issue.

Biden’s greatest political liability, meanwhile, may be immigration. The Democrat’s administration has struggled to limit the number of immigrants entering the country at the U.S.-Mexico border. His allies privately acknowledge the issue is a major political liability heading into the fall.

Trump loves nothing more than highlighting illegal immigration, so expect him to pound Biden on the issue.

At the same time, Biden will face tough questions about his leadership in the war between Israel and Hamas. The president has alienated some would-be supporters on both sides given his staunch support — and occasional criticism — of Israel.

He’ll have a major opportunity to defend his record on the complicated issue Thursday night. It won’t be easy.