The Cook Political Report: “After every major presidential and midterm election, the Democratic data firm Catalist releases a comprehensive analysis of the composition and partisan leanings of the electorate. What distinguishes their analysis from election night exit polling is that it integrates data like vote history, Census data and Catalist’s own polling and modeling, which can give us a more fulsome view of who joined the electorate, and — as importantly — who dropped out of it. The Catalist “What Happened” report, shared first exclusively with The Cook Political Report, finds that Vice President Kamala Harris’ 2024 loss was due to two key factors: She lost roughly two points of support among those who turned out in 2020, and new and infrequent voters failed to materialize for Democrats as they had in previous elections.‬ For the first time in Catalist’s dataset, both infrequent and new voters — groups that tend to be younger and more diverse than the electorate at large — fell below 50% support for a Democratic presidential candidate…”

See also the Washington Post [no paywall] – The 2024 election was even weirder than we thought. An expansive new report challenges early theories about how Donald Trump won: “….Lots of reporting before November focused on a widening gender gap in many polls leading up to the first presidential election after Dobbs v. Jackson Women’s Health Organization. This is why AP VoteCast’s initial estimates came as a surprise, as they implied the gender gap remained stable in 2024, and that Donald Trump drew a roughly equal amount of additional support over 2020 from men and women. Catalist, however, suggests that these numbers were extremely off base, and that Trump’s gains were concentrated almost entirely among men: Though he gained just two points of ground with women, he gained nearly 11 points with men, widening the gender divide by 9 percent on margin. This marks its sharpest increase in at least the past decade of U.S. politics…”