Ruy Teixeira questions the conventional wisdom that demographic trends point toward future Democratic victories.

Nothing makes the Democratic heart beat faster than a sense that the demographic wind is at their back. They love the idea that they can safely disregard all that messy persuasion stuff to focus on rising demographics and mobilize, mobilize, mobilize.

The current demographic darling is the youth vote, which did indeed perform well for the Democrats in 2022. But much commentary has gone beyond that simple, true observation to portray the youth vote as a tsunami about to overwhelm the Republican Party. …

Turnout by age goes up and that affects generations a lot. This is another factor that leads to confusion. As generations age, their turnout (defined as percent of eligible voters that cast a ballot) goes up for many years simply because older voters vote at a much higher rate than younger voters. In fact, the agre-turnout gradient is particularly sharp among voters in their twenties and thirties, which of course complicates interpretations of turnout performance among Millennials and Gen Z. This makes it harder—or should make it harder—to ascribe any turnout magic to these generations.

Presidential elections are different from congressional elections. In 2022, young (18-29) voters defied the prevailing winds and Democrats improved their margin among these voters by 5 points relative to 2020. But congressional elections and presidential elections can be quite different, not least because a different, larger group of voters shows up for presidential elections. That affects the attitudinal complexion of all demographic groups, especially a volatile group like young voters.

Consider that Democrats carried the two party vote among 18-29 year olds by 36 points in 2018 only to have that margin decline by 12 points in 2020. And that was with Trump on the ballot. Right now, polls tend to show Democratic weakness among young voters moving into the 2024 cycle.