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The nearly 40 minutes of Donald Trump standing on a stage near Philadelphia, belting out a playlist and dancing like a bozo uncle at a wedding easily became fodder for meme makers, late-night hosts and the former president’s outspoken haters. But it also presented an opportunity – albeit a potentially dangerous one – for his rival who wanted to keep him out of the White House.

Kamala Harris and her campaign seized on this strange incident. “Trump seems lost, confused and frozen,” the @KamalaHQ account posted on X with a clip of the event. Harris went further, sharing that message from her own account with the added joke: “Hope he’s doing well.” Trump’s mental acuity has long been one of those persistent unknowns — especially given his refusal to release his medical records. Monday’s event, which started as a policy-based question and answer session with North Dakota Gov. Kristi Noem and evolved into a dance party after two attendees needed medical attention, was the final moment when that murmur grew into a roar that could not be ignored.

But there is a risk here that Democrats would do well to take seriously. Yes, if the 78-year-old Trump wins a second term, he would ultimately become the oldest person to ever be president. But it’s also worth remembering this: Nearly two-thirds of voters this fall are expected to be over 45, and one in four is expected to be 65 or older. It’s one thing to pursue someone’s potential ability to do the job, but it’s another thing entirely when it seems like outright ageism. And for now, Harris’ approach could alienate some voters who see it as the latter.

When 81-year-old Joe Biden decided in July that he would not seek another term as president, Democrats clearly found a potential advantage here. With 59-year-old Harris leading the party, Democrats were no longer carrying past-the-prime skepticism. Instead, what had been one of Biden’s most persistent slugs suddenly shifted to Trump, who is only three years his junior. Harris, on the other hand, is a powerful figure who will make history, clearly has the ability to get under Trump’s skin and has performed exceptional resuscitation on what had been a languishing Democratic Party.

The risk here, however, is not entirely new to Harris’ campaign team in Wilmington, Del. Some of them were involved in Barack Obama’s 2008 campaign against 71-year-old John McCain. The top Obama strategists of 2008 were crystal clear in their edict: incorrect And confused were acceptable ways for the campaign to describe McCain, but old And expired were not.

The cryptic attempt was a continued burden on the McCain team, which openly accused Obama’s stance of ageism. Nevertheless, Obama’s campaign continued with coded terms; both John Kerry and Susan Rice were “confused” to describe McCain. In Obama’s inner circle, they were not about to push aside what they saw as legitimate questions about McCain’s ability to do the job just to sideline those who shouted anger. (Harris’ team also includes professionals from Hillary Clinton’s 2016 bid, in which age was a double-edged sword, as Trump was 70 and she was 69, and she faced more hushed whispers about her abilities.)

Of course, Obama came out on top. In that election, 53% of that electorate was over 45 years old. According to exit polls, the cohort was evenly split 45 to 59. The only age-based group that favored McCain was the 60 and older crowd, which he won 51% to 47%. (Obama saw negligible improvement in both groups over Kerry, the 2004 nominee.)

The balancing act is a difficult task, and one that Harris’ team and its supporters must be extremely careful about. In the latest CBS News poll, voters between the ages of 45 and 64 are siding with Trump, 53% to 46%. Among voters aged 65 and older, this increases to 57% to 42%.

Perhaps voters have become numb to Trump’s stream of norm-shattering, head-scratching behavior. Perhaps their judgment of him is set, regardless of his behavior in the final weeks of the campaign. Maybe Trump actually is the candidate most Americans would like to see as leader of the country and his decision to spend an evening playing tunes instead of making the same boisterous speeches in front of the voters. And just maybe, many voters are learning about ageism in their own way, seeing latent signs of it everywhere they look—perhaps including in a hard-fought presidential campaign.

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