It is the first debate ever between two men who have both been president, which creates a unique dynamic for the nationally televised set-to. And it comes just 14 weeks before the earliest early voting begins.

Both men, who remain presumed nominees until their party’s convention in July and August, are the oldest to compete. And Biden, who turns 82 this year, sets a new White House age record every day, even the 40 percent he spends on vacation.

The debate on CNN at 9 p.m.Eastern will be the first opportunity for millions to see each man live and together and to judge their responses to unexpected questions, assuming another CNN commentator didn't leak them to the Democrat again, as Donna Brazile did for Hillary Clinton in 2016. 

But more importantly, they will judge their appearance, behavior, and demeanor under pressure. While both men will argue over what they said and didn’t say, impressions will be the key takeaway for many.

Based on their widely different White House records, which experienced chief executive currently appears capable of being commander in chief again in these troubled times, given their advanced ages and existing images in voters’ minds?

Either man could pull a surprise. Trump is a showman famous for saying, "You're fired!" on his top-rated TV show. What if, in his closing statement, the former president announced his VP pick? "You're hired!"

Trump’s anger appears to have faded somewhat since his tumultuous, argumentative days in office when no slight was too small to require an angry presidential rejoinder, even online. 

So, the lack of a raucous studio audience and microphones that can be muted may actually help him. Trump loves his audiences loving his rhetorical punch-backs. Others, not so much.

And if President No. 45 can behave, well, presidential unlike the first 2020 debate, that could go a long way toward swaying voters, who disdain both men, to go for the Republican this time as the least-worst option and make him President No. 47.

Trump might remind viewers obliquely of Biden’s obvious mental and verbal challenges, maybe with a Reaganesque, “There you go again.” But three years of witnessing those accumulating brain freezes, incoherent mumbles, and blank stares have already baked them into most minds. (Watch this disturbing video.)

Here are five straight minutes that show exactly why the special counsel noted Biden's diminished mental fitness pic.twitter.com/u1ToosAKyz

— RNC Research (@RNCResearch) February 11, 2024

For Trump to recite such cringeworthy moments, as he often has on the trail, would only confirm he’s a bully, potentially igniting an unhelpful sympathy factor for the older man. A silent, rolling of the eyes would suffice, as many of us have done witnessing senior moments in our own families.

And the fact is, the former president, who turned 78 nine days ago, has committed a few spoken errors himself in recent months, confusing people like Nancy Pelosi and Nikki Haley, though nothing on the scale or frequency of Biden’s serial confusions. 

More effective would be Trump detailing his own plans and critiquing Biden’s multiple disastrous policies – killing energy independence, inflation, the lethal Afghan exit, a $1.9 trillion deficit, selling off our oil reserves, admitting 10 million illegal immigrants, forcing all taxpayers to repay college loans for a select sector (in defiance of the Supreme Court).

And Trump should skip the worn-out 2020 election whining, just as Biden should pass on his Jan. 6 plaints.

Biden has the biggest debate challenge, just 90 minutes of opportune moments to weaken the hardening image of him that polls have confirmed, that a large majority of voters simply do not believe he is up to the job now, let alone until 2029. 

That even though he falls off his bike, tumbles on airplane steps, trips on stage, walks out mid-ceremony, looks lost often, and takes on that glassy-eyed, open-mouthed stare of a brain freeze, he is fully capable of leading the Free World.

One report on Biden’s debate prep has him practicing standing up for 90 whole minutes. Has that kind of lame stamina really become a presidential attribute? 

Replacing the senile Biden narrative is a tall order for sure. Everyone has seen his frailty in loved ones and knows you don't recover. Aides tipped reporters to expect some surprises, which kind of ruins the surprise. 

As an ultimate showman, Trump could steal the entire debate. On Saturday, he told NBC News' Jake Traylor that he has decided on his VP partner, has not told them, but they'd be attending the debate.

Trump gets the last closing statement. He could make his VP announcement at the very end and, from a news import viewpoint, basically blow up the previous 90 minutes of blather.

Since we can safely rule out Biden cartwheeling onto the stage, his "surprise" will be something more like goading Trump into an outburst, such as repeatedly calling him a convicted felon.

Trump should simply smile.

That would be a two-edged sword for Biden anyway since Trump’s predictable felony conviction in his Manhattan lawfare trial prompted more than $141 million in May campaign donations.

The former president, in my opinion, has made a mistake in recent weeks detailing Biden’s mental lapses. Confidence is good. Cocky, not so much. You don't hear coaches put down their next opponent. They build them up, so a W means more.

Trump audiences do love that attitude. Too late, Trump backed off of that this past week. But it has set the Biden's debate bar far too low.

Biden gets two commercial breaks to catch his breath. And you won’t get to see him shuffle onstage. But if Biden comes out and doesn’t drool or pull a “Dave” collapse at the podium, his sympathetic media and echo chamber will pronounce his performance reassuringly fine.

That’s what the people pulling his strings are counting on with this early debate’s first impression enduring into the fall. 

Watch some more of that video of Biden brain freezes, which occur now in virtually every public appearance. Then, compare it with his State of the Union performance here in March after he was out of the public eye for hours (Biden begins speaking at 9:20). 

The incumbent did look old. And he’s taken to randomly saluting civilians for some reason. At times, he shouted and whispered strangely, but he didn’t look demented. If he pulls that off again in Atlanta, that could put the spotlight back on Trump’s behavior, the focus of Democrats’ massive ad campaign.

That wasn’t a stunt double speaking to Congress. Clearly, there’s some unexplained reason Biden has routinely fled to Delaware or, this week, Camp David, where visitors are not documented. Mental declines in golden years vary by individual and even by the day. But there is no recovery from old age. 

Biden certainly appears to be getting some kind of treatment for something. We won’t know what it is for years, of course. 

Online speculation has suggested Biden might be getting Donepezil, a medicine administered orally daily or by patch. 

It’s used to slow the inevitable effects of dementia associated with Alzheimer’s disease. Its goal is to reduce confusion, improve awareness, memory, and the ability to function in daily life, exactly what Biden needs.

However, Donepezil does not always work, according to doctors and family members interviewed, and its benefits are temporary.

And like all medicines, Donepezil has side effects. The major side effect, according to the Mayo Clinic, is diarrhea. Other side effects can include unusual fatigue and weakness, drowsiness, unsteadiness, blurred vision, and loss of bladder and bowel control. 

At this month’s D-Day memorial ceremony, Biden appeared to start sitting down. But he stopped halfway, waited, then said something to his wife, who then escorted him away before the event ended.

At the G-7 meeting in Italy last week, participants said Biden appeared unfocused. At one event, as I reported in a recent column, Biden wandered off from other leaders as if he heard an ice cream truck.

It’s still a good while until the voting. Much can still happen before Nov. 5. Even with party conventions approaching in mid-July and late August, Americans tend to tune out politics in these peak vacation times.

I have written previously of my personal surprise if, given the accumulating negative evidence and polls, Democrats actually proceed with a Biden renomination two months from now.

Given that same encouraging evidence for Republicans, voters and media supporting Trump often act as if a Trump victory is almost a given. It is not.

True, Joe Biden’s job approval on all major issues, especially the economy and immigration, has been and remains deeply underwater. And no incumbent president since 1948 has won reelection with an overall job approval mired in the thirties.

The problem is polling, It’s indicative of late June, of course, not predictive of early November. But the results have been and remain quite close for either side to presume victory. 

The latest RealClearPolitics average nationally is a virtual tie, with Trump holding a minute lead, 46.1 to 45.2. 

What matters in reality, however, are swing states. The RealClear average in seven of those has Trump ahead with the same numbers and slim margin.

Four years ago, on this same date, Biden held a swing state lead of 9.8 points. He actually won them by 4.5 points. 

Eight years ago, on this same date, Hillary Clinton led in them by 5.8 points. She did win the popular vote by 2.1 points. But she took several typically Democrat states for granted. Trump didn't. And his votes came in just the right states to capture the Electoral College, 304 to 227.

So, polls can be wrong. Respondents can lie. They can change their mind. Which at the end here brings us full circle to the beginning of this column: 

Thursday’s debate is crucial in these polarized times. Trump loyalists will believe he won no matter what happens. Trump haters will predictably approve of Biden’s winning performance.

Millions of potential voters who do not watch or listen will get their impressions in the aftermath from friends or seeing snippets online.

Unless, of course, something unexpected happens. Which, as they say in football, is why they play the game.