Philip Bump says Biden had a bigger mandate than Trump has: A lot of early analysis of the 2024 presidential election has suffered from three overlapping problems. First, that vote margins can be influenced by changes in turnout as well as changes in vote preference. If voters stay home, the candidate they would have supported receives fewer votes. And it looks like a lot of 2020 voters stayed home in 2024. But — second — not as many as one might have thought in the first few days after the election. Many immediate analyses of what happened exaggerated the decrease in Democratic votes or suggested that Donald Trump won an outright majority of votes cast, both errors that were a function of failing to consider (particularly) California’s sizable, slow-to-count vote total. The third problem is that the shift to Trump in the voting — real and widespread — is being conflated with broad support for Trump, which is far less dramatic. It’s the difference between noting that exit polls show Trump fared much better with voters under 30 than he did in 2020, and acknowledging that he lost that age group to Vice President Kamala Harris. He didn’t lose them by as much, but he still lost them. Which, again, overlaps with other problems. Our analysis suggests that this improvement came as the number of younger voters fell relative to 2020. Harris lost votes relative to Biden; Trump got about the same number of votes from people under 30 that he got four years ago — according…