Quantifying the Electoral “Vibe Shift.” A Naturally-Occurring Experiment on President Biden’s Decision to Exit the 2024 Presidential Race

Abstract. President Joe Biden’s unprecedented decision to exit the 2024 Presidential race three and a half months before election day – following a disastrous debate performance – may suggest that he came to view his would-be nomination as detrimental for general-election turnout, as well as the success of Democratic candidates down-ballot. Yet, previous public opinion research casts doubt on whether presidential debates influence voters’ electoral attitudes and behavior. We contribute to this literature by analyzing a naturally occurring experiment surrounding the incumbent President’s decision to exit the 2024 race; a period in which we fielded the second wave (NWave 2 = 831) of a nationally-representative panel study (NWave 1 = 1,400), with random invitation assignment (from the original response pool) throughout Wave 2. Pre-registered difference-in-difference (DID) analyses reveal no evidence of significant turnout or down-ballot effects across either the US adult population or partisan subgroups. However, post hoc tests reveal substantial gains in excitement about the 2024 campaign across both the general population and (especially) among self-identified Democrats after President Biden’s decision to drop out. Elevated excitement coincided with (a) increased belief in core democratic principles, and (b) increased donation to Democrats up and down the ballot; both of which, we argue, have important normative democratic implications.