The debate hurt Biden, but the real change has been happening for years

After the first presidential debate, a chorus of top Biden allies and campaign leaders have delivered a simple message: The race has not fundamentally changed.

In a sense they are right.

Far from upending the race, Wednesday’s latest New York Times/Siena College poll reinforced the central dynamic of the election: the political decline of President Biden, who no longer has the advantages that enabled him to defeat Donald J. Trump four years ago.

Overall, the poll shows Trump ahead of Biden by six percentage points among likely voters and nine points among registered voters nationwide. In both cases, it’s a three-point shift in Trump’s favor since the last Times/Siena poll, which was conducted just before the debate.

Historically, a three-point swing after the first debate is not unusual. In fact, it’s the norm. Over the last seven presidential elections, the person generally considered the winner of the first presidential debate has gained an average of three points in post-debate polls. Sometimes the swing lasts; other times it disappears. But either way, debates typically don’t fundamentally change a race.

As far as the polls go, this debate is no exception — at least not yet. The debate may ultimately prove to be the breaking point for Democratic politicians considering whether to endorse Mr. Biden, but the polls do not show that the debate has completely changed public opinion of the candidates. Instead, the debate has exacerbated Mr. Biden’s political liabilities, which had already jeopardized his reelection chances.

Four years ago, it was the absence of major political obligations that allowed Mr. Biden to defeat Mr. Trump. He won the Democratic nomination and ultimately the presidency because he was a popular, relatively moderate, broadly acceptable candidate who could unite the politically diverse electorate that disliked Mr. Trump. At the time, polls showed a majority of voters had a favorable opinion of Mr. Biden. It was just enough for him to win the Electoral College by a narrow margin — by less than a percentage point in the decisive states.

The polls showed that Biden was no longer a widely accepted candidate, and therefore no longer ahead of Trump. Long before the debate, his approval and popularity ratings had fallen well into the danger zone for an incumbent president. More ominously, his numbers were falling even though the conditions for a Biden comeback always seemed imminent. Inflation was falling. The general election was heating up. On paper, an incumbent president should have been the favorite, and his opponent was a candidate accused of multiple crimes and recently convicted of a felony.

But today his approval rating stands at nearly a net 10 points lower than before the 2022 midterm elections, when inflation was running at more than 7 percent. As the economy and consumer confidence have improved since then, perhaps the best explanation for this steady erosion is growing concern about his age.

The poll shows that by all measures, the debate took a further toll on the public’s already diminished opinion of him. His approval rating dropped two points after the debate, from 38 percent to 36 percent. For comparison, it was 52 percent in the last Times/Siena poll before the 2020 election.

The share of voters who said Biden is “simply too old to be an effective president” rose five points, from 69 percent before the debate to 74 percent. Just 36 percent said Biden was too old in June 2020.

These modest post-debate shifts aren’t necessarily significant in the grand scheme of things. They’re certainly not “fundamental” changes. What’s fundamental is a 15- or 30-point shift over four years. While Mr. Biden may sometimes perform better than he did last week, the long-term trend suggests that the cumulative effect of countless interviews, speeches, photos and social media posts has left much of the public with the impression that he is no longer as well-equipped to serve as president.

For much of the cycle, the bullish case for Mr. Biden rested on the assumption that voters would increasingly focus on Mr. Trump’s shortcomings as the campaign intensified. In this view, disengaged voters would focus on democracy and abortion and vote, as many did in the midterms.

Indeed, Mr. Trump remains as unpopular as he was four years ago. In fact, the share of voters with a favorable opinion of Mr. Trump after the debate is almost exactly the same (43 percent among likely voters) as it was in the Times/Siena polls so far this year (44 percent); and as it was before the midterms (43 percent); or as it was before the 2020 presidential election (44 percent).

But in last week’s debate, Mr. Biden failed to make good on that optimistic case. Millions of voters tuned in for a matchup between Mr. Biden and Mr. Trump, and the focus ultimately fell on Mr. Biden’s age — and will continue to do so for days or weeks to come — rather than on the issues that could win him the election.

Historically, shifts in the polls after debates can be fleeting, with candidates thinking that the losers could bounce back in the next debate or turn the spotlight back on their opponent. With many Democrats wondering whether to back Mr. Biden, it’s hard to see how the race will move away from questions about the president’s age anytime soon. Worse, Mr. Biden’s record suggests he may not be able to convince skeptics that he’s fit for the job. But if Mr. Biden can overcome his party’s concerns, Mr. Trump’s low positive ratings suggest there’s still a path for a close race.

The Times/Siena data offer less evidence to support another reason why polls can shift after a debate: the tendency of supporters of the consensus winner to respond to polls in disproportionate numbers. In contrast to the pre-debate poll, Democrats and Republicans responded to this week’s poll in nearly equal numbers (after accounting for race), just as they have in nearly every Times/Siena poll in the past year. If our latest poll was indeed a little too favorable to Mr. Trump, it’s possible that he gained even more ground than the three-point shift shown here.

There is no way to know for sure whether Mr. Biden’s age is his only problem, a major problem, or just one of many. Perhaps lingering resentments over high prices and the border would still give Mr. Trump an edge over a hypothetical younger Mr. Biden. The economy, after all, remains the top issue for voters in the polls. Or perhaps voters yearn for changes they doubt Mr. Biden and the Democrats — who have held the White House for 12 of the last 16 years — can deliver.

But if Biden can’t convince voters — or Democrats — that he’s fit for the presidency, the other challenges may not matter.