When does old become too old for voters?

Just because it's easy to blame Biden's age for his political woes doesn't mean it is. There is no doubt that voters are concerned, but it is very difficult to know how much support it will cost Biden in the polls. For example, we can't know what his approval rating would be if he were 10 or 20 years younger. Perhaps it would be almost as low, because of the border, the Middle East, past inflation, lingering post-pandemic resentment and worry — in addition to the corrosive effects of partisan polarization.

Why can't we know? The age problem is not the same as economics, where easily measurable data helps us understand its meaning. We know that 10 percent inflation or 10 percent unemployment could be enough to cost the president a re-election. We've seen it before, based on decades of hard data. In contrast, the severity of Biden's age problem is almost entirely in question. That perception is largely subjective – based on what he looks and sounds like, not just the fact that he's 81. (Mr. Trump is 77.)

Superficial and subjective issues like these are difficult to analyze, as evidenced by the terribly wide range of reactions at Mr. Biden's news conference on Thursday. Even a question as simple as “why do voters think Biden is too old, but not Mr. Trump?” is difficult to answer. Clearly voters believe that, but the likely explanation is as superficial and subjective as the feelings of individual voters. Subjective obviously does not mean unimportant. Even the most superficial factors such as appearance or voice depth can play a powerful role in vote choice. It appears that Mr. Biden has crossed an invisible line that determines whether a candidate is not only old, but “too” old in the eyes of many voters; Mr. Trump has not done that.

Moreover, the questions about Mr. Biden's age are almost entirely without precedent in the era of modern elections. No president has ever been so concerned about his age — not even Ronald Reagan in 1984, who was eight years younger than Mr. Biden this cycle. That's exactly why it's easy to imagine how concerns about his age could be politically powerful. But it also means that we have never seen the political impact of something like this before.

Almost every election features something unprecedented, with the potential to shake up the usual political patterns. In the last four cycles alone, we have witnessed the first Black major party presidential candidate, the first female candidate, the first with no military or elected experience, the first modern election in the midst of a pandemic, and so on. In each of these cases, experts and analysts speculated – quite reasonably – about whether these new candidates or circumstances might produce an unexpected outcome.