The slide in Democratic identity poses more than one risk to Biden

Every month, Gallup asks Americans to identify their political party — Democrat, Republican or independent. If the response is “independent,” they’re then asked whether they tend to lean toward one of the two major parties.

At the end of each year, Gallup averages the responses. In data released Friday, Gallup reported that 2023 had reached two extremes: the percentage of Americans who identify as independents tied its high and the percentage who identify as Democrats hit a new low.

It’s by now a trope to observe a news event and declare that it’s bad news for President Biden. But this is bad news for President Biden — for reasons that go beyond the obvious.

You can see the independent and Democratic shifts below. Just over a quarter of the public identified themselves as Democrats throughout 2023, a low point in the blue bars on the graph below. The gray section — independents — has gotten wider over time, landing at 43 percent in 2023. (The same percentage was measured in 2014.)

When we combine the two, something interesting happens. The combined Democrat/Democrat-leaning independent value also is a new low.

It’s not just that people aren’t joining the Democratic Party — or, more importantly, identifying themselves as members of the party. It’s that this isn’t being offset by the addition of independents who vote with the party.

That is an increasingly important part of each party’s voting bloc. The percentage of the Democratic bloc that is Democrat-leaning independent hit its third-highest point in 2023, surpassed only by 2017 and 2020. The percentage of independent leaners in the GOP’s voting bloc hit a new high.

In other words, both parties are now unusually dependent on votes from people who aren’t members of the party.

When Biden’s approval ratings started to plunge in 2021, it was largely a function of self-identified independents. Over time, polls measured a decline among another important demographic group: young people.

Those are probably linked. Even just within the Democratic voting bloc, as measured in the 2022 General Social Survey, younger people are more likely to identify as independents who lean toward Democrats. As the age of voters who vote with the Democrats increases, so does the percentage of those voters who identify as actual Democrats.

In the 2020 election, younger voters offered Biden the widest margins of support, as data from Pew Research Center shows.

As the 2024 presidential contest has heated up, Biden has struggled in polls pitting him against the likely Republican nominee, Donald Trump. In part, that’s because of his unusually soft support from younger voters, who retain strong disapproval for his presidency.

It’s hard not to posit (as I did in November) that this is partially rooted in the distance between younger voters and the party Biden leads. Over time, analysis of election results found increasing loyalty in presidential voting by partisans. But if you’re someone who identifies as an independent but doesn’t like Biden? There would very conceivably be less of a pull toward coming out to vote, much less for Biden.

This could change. The idea of Trump regaining the presidency may, as it did four years ago, spur people who view Biden negatively to come out to the polls. The traditional pull of partisan loyalty may be replaced by the increasing potency of negative partisanship — voting based on hostility to the alternative.

Or, these Democrat-leaning independents may be more likely to stay home. In which case Biden has a big hole to fill.