I’m old, and rather famously, old people struggle with change. The world as they’ve known it proceeds for decades according to certain rules until, one day, it doesn’t. And when it doesn’t, that’s unacceptable.

If you’re into politics, one of those time-honored rules is that presidential debates don’t matter. Millions tune in, shout at the television, argue over who won or lost, and when the smoke clears, there’s zero evidence that it moved any meaningful number of votes.

That’s not my opinion. To quote Ron Burgundy: It’s science.

Some old people do better than others in adapting to change, though. On June 26, a day before Joe Biden and Donald Trump met to debate, Old Man Goldberg made a bold prediction. “I have changed my mind,” he declared. “This week’s presidential debate matters.”

He would be vindicated in that prediction, and in this one: “Fair or not, if Biden has a major malfunction, it will be an irreparable confirmation of voter concerns about his age. I would expect the whispers about replacing him on the ticket to become shouts almost overnight.”

Pretty good—but he wasn’t done. Jonah also imagined a debate victory scenario for Democrats. “Most voters do not like [Trump] and pretty much never have,” he reasoned. “If he leans into the traits that turn them off—if he follows that age-old advice, ‘Be yourself’—and Biden is even modestly reassuring, the double-haters and other undecideds could easily break for the president.”

Swap in “Kamala Harris” for “Biden” and “vice president” for “president” in that passage, and you have an astute prediction of how last week’s presidential debate would play out politically.

Today’s RealClearPolitics national polling average reveals a small but unmistakable bounce for Harris since she and Trump faced off nine days ago. She stood at 48.4 percent on September 10, the day of the debate, a figure that was practically unchanged since mid-August. She’s since gained a full point and is currently polling higher than she ever has (or Biden ever did).

Of the 10 national surveys conducted after the debate, she’s touched 50 percent or better in seven of them. And according to a New York Times national poll published on Thursday (which, ironically, had her merely even with Trump at 47 percent apiece), there’s good reason to believe it’s because of the debate. “Ms. Harris fared strongest among the 80 percent of voters who said they had either watched that night or seen clips afterward, winning among those voters,” the paper reported. “Mr. Trump was winning a majority of the far smaller share who had either only heard about the debate, or had not heard anything about it at all.”

Every fiber of my aged, wrinkly, flabby body resists admitting it, but the truth can no longer be denied: Debates matter.

At least, they do this year.

If ever there were a campaign where debates shouldn’t matter, this is it.

The electorate is hyperpolarized, leaving few persuadable voters, and the three candidates who’ve led their party’s ticket since January are the three most familiar “known quantities” in politics. Every voter in the country has formed strong, all but unshakable opinions about the current president, a former president, and the current vice president, one would think. Nothing any of them can say will change any minds.

Instead, we’ve had not one but two debates that moved the needle, perhaps decisively. How?

Well, despite their high public profiles, Biden and Harris actually were unknown quantities to voters in important ways. The president was at the center of a months- or yearslong White House cover-up of his cognitive decline. The public always suspected it, per the many polls that showed rising anxiety about his age, but not until June 27 did voters get the smoking gun that proved it. Once they did, he was immediately rendered unelectable.

The fact that Biden hung on as nominee for so long before yielding to reality allowed Harris to become an unknown political quantity unlike any other national candidate in recent memory. All of the ways in which aspiring presidents are usually vetted and diminished—primaries, primary debates, opposition research, interviews, the endless grind of the campaign trail—were gracefully sidestepped by the switcheroo. She claimed her party’s nomination as a “blank slate.”

Is it any wonder, then, that the two debates would prove unusually influential this cycle? Both were opportunities for voters to fill a yawning gap in their knowledge about the Democratic nominee that wouldn’t have existed in a “normal” campaign. They needed to know whether Joe Biden was up to the job, then they needed to know if Kamala Harris was up to the job.

In both cases, they got their answer. The polls moved accordingly.

Harris’ peculiar—but clever—campaign strategy also gave the debate more weight than usual. Typically, a debate is just one more (albeit higher-profile) opportunity for voters to hear a candidate explain their plans to govern. In Harris’ case, due to the truly shocking extent to which she’s dodged the press, it was effectively the only opportunity. By refusing to answer questions regularly, she raised the stakes of the debate such that her fitness for the presidency was destined to be defined by how well or how poorly she did.

If she blew it, she might not recover. But if she aced it, she might ease the doubts of swing voters who had reserved judgment about her to that point and be rewarded with real momentum in the polls. She bet the political equivalent of her mortgage on the latter. She appears to have won that bet.

As cynical as Harris’ omerta strategy has been, and as unfair as it is for Democrats to profit from denying voters important information about both of their nominees this year, it’s hard to argue with the results. Check the trend in her favorability ratings since the switcheroo and you’ll find that it’s nearly a vertical line upward. From the start, she seems to have calculated that the more specific she gets about policy, the harder it’ll be for her to posture as the “change candidate” swing voters are dreaming of. In agreeing to discuss her plans, she’ll be forced to either duplicate large chunks of Biden’s agenda, which isn’t so change-y, or to tack to the left to set herself apart from him and Trump, which is change-y but in the wrong direction.

The closest she can get to popular “change” is to turn herself into the most generic Democrat she can be and hope that enough voters find that preferable to Trump 2.0. “In a ‘vibes’ election, a vibes debate could matter,” Jonah presciently wrote back in June. A “vibes” election is the only election Harris can win; go figure that her strategy wouIld reflect that, and that she would have looked to the debate as a potential inflection point.

If all of that isn’t enough to explain why the debates might carry extra weight this year, there’s also the Trump factor.

Centuries ago, when Jonah and I were young, presidential debates reliably involved two candidates who were fit for office and knew their stuff on policy. Under those circumstances, it made sense that debates didn’t drive many votes. Realistically, how many persuadable viewers would be so dazzled by one candidate’s agenda relative to the other’s that they would emerge with a strong electoral preference after just 90 minutes of exposure to it?

With Trump, there are so many doubts about his own fitness that an especially strong or especially weak performance by his opponent might instantly cast him in a different light for voters who are wavering. Put him next to a mumbling Joe Biden and he’s the lesser of two evils; put him next to Harris and suddenly he’s the greater. If he had rambled about immigrants eating cats at the first debate, that would have been a minor story relative to Biden’s condition. At the second debate, with nothing to distract viewers, it was the story.

In other words, Harris didn’t just do well for herself; she benefited from the contrast with a crazy person. And while that didn’t hurt Trump much after his debates in 2016 and 2020, maybe it matters more to persuadable voters after a coup attempt, dozens of criminal convictions, and nine long years of exhausting nonsense.

Add all of that up and it amounts to neither candidate having a strong incentive to debate again.

Trump has already wriggled out of a rematch and won’t change his mind unless Harris starts to really pull away. He’s better off denying her another chance to impress late-deciders than gambling on his ability to sound cogent and competent, something he’s never successfully done in three cycles of trying.

And Harris, having won her mortgage-sized bet on the last debate, is probably better off not pressing her luck. Trump would learn from his mistakes to some degree and prosecute the case against her more effectively next time. (How could he do worse?) And even if he didn’t, there’s nowhere for Harris to go but down when the moderators press her to define her policies more specifically on a big stage. Change-y “vibes” require vague answers.

Besides, why should she take another major risk when the race appears to be trending her way—especially in the states that matter most?

On Thursday, the New York Times’ Nate Cohn flagged a confounding result in his paper’s new poll, which had Harris tied with Trump nationally but up 50-46 in all-important Pennsylvania. That’s not supposed to happen: In the modern United States, the national popular vote dependably tilts toward Democrats while the swing states end up on a razor’s edge. How can Harris be doing better in the most important battleground than in the country writ large?

Cohn isn’t sure, but he noticed that other high-quality pollsters have also recently found decent leads for Harris in the northern swing states yet more modest leads for her in national polling. And that’s consistent with the results of the 2022 midterms, where Republicans ended up losing a seat in the Senate and wildly underperforming in the House—despite winning the national popular vote.

The traditional expectation of reddish battlegrounds in a bluish country was reversed that year. Could it happen again in November?

Theories in the affirmative range from demographic realignment, with Trump shedding white support in swing states and gaining nonwhite support elsewhere, to local law-and-order anxiety in coastal blue states holding down Democrats’ margins there but not nationally. But here’s another possibility: Harris had a good debate, and in a “vibes” election a good debate might logically matter more in battleground states than it does nationally.

The blockbuster television ratings in Pennsylvania confirm that voters there paid closer attention to the debate than Americans did generally. (Of course, it was held in Philadelphia.) Post-debate surveys of the state have been encouraging for Harris too, with four different well-regarded pollsters now giving her leads of 3 points or better and boosting her to her best number in the Pennsylvania average to date. The trendline suggests a meaningful bounce might be underway.

“Only 42 percent of voters had rated her favorably in Pennsylvania in early July,” the Times said of Harris in its new survey of the state. “Now that figure stands at 51 percent—a remarkable improvement.”

Maybe all of that is a statistical mirage. Cohn points to evidence in the data that Democrats in Pennsylvania became more likely than local Republicans to answer the Times poll in the debate’s aftermath, skewing the sample. It may not be that Harris changed any minds, in other words, so much as that she gave her voters a fleeting burst of enthusiasm relative to Trump’s. In fact, her 50-46 lead is identical to the lead the Times found for her in its July poll of Pennsylvania.

But there’s also reason to believe that swing-state voters are dialed into this campaign to an unusual degree even relative to the swing-state voters of past cycles. A few weeks ago, Gallup found national voter enthusiasm was at the highest level it’s been this century at this stage of the race. When asked how much thought they’d given to the election, the share who said “quite a lot” was easily higher as of August than in any other race since 2000. 

If interest in the election is that intense nationally, imagine what it’s like in Pennsylvania. And if it’s that intense there, why wouldn’t a rout at the one and (probably) only debate between the candidates matter more than in elections past?

My theory of most undecided voters has been that they want to find reasons to vote for Trump but have enough misgivings about it that they’re struggling to rationalize doing so. They need just a little bit more from him to talk themselves into it. But maybe I’ve had it backward—maybe Old Man Goldberg was right that they want to find reasons not to vote for him and have been looking for a little more from Harris to justify not doing so. On that point, it’s notable that her polling both nationally and in Pennsylvania rose quickly after she replaced Biden on the ballot but then stalled out in mid-August, as if her cipher of a campaign had picked all the low-hanging anti-Trump fruit but couldn’t get up into the higher branches.

A single solid 90-minute debate in a normal political environment where voters are focused on policy couldn’t possibly boost her up, particularly when she’s been so dodgy about answering questions elsewhere. But in an abnormal environment, where the choice involves a candidate who will assuredly try to overturn the election results if he loses—and where voters’ intensity reflects their keen awareness of that fact—why not? Harris’ performance gave those higher anti-Trump branches the little bit of “more” that they needed to get to yes, it seems. Now, suddenly, her momentum is un-stalled.

So, yes, debates matter! At least they do when you have a “blank slate” at one podium who’s being judged mostly on whether she can muster the bare minimum of presidential “vibes” needed to qualify as the lesser of two evils relative to someone who’s actually evil. If Republicans didn’t want it that way, they should have chosen a different nominee.