The present research directly replicates past work suggesting that metadehumanization, the perception that another group dehumanizes your own group, erodes Americans’ support for democratic norms. In the days surrounding the 2020 US Presidential Election, American political partisans perceived that their political opponents dehumanized them more than was actually the case. Partisans’ exaggerated metadehumanization inspired reciprocal dehumanization of the other side, which in turn predicted their support for subverting democratic norms to hurt the opposing party. Along with replicating past work demonstrating metadehumanization's corrosive effect on democratic integrity, we also contribute novel insights into this process. We found the most politically engaged partisans held the most exaggerated, and therefore most inaccurate, levels of metadehumanization. Moreover, despite the socially progressive and egalitarian outlook traditionally associated with liberalism, the most liberal Democrats actually expressed the greatest dehumanization of Republicans. This suggests that political ideology can at times be as much an expression of social identity as a reflection of deliberative policy considerations, and demonstrates the need to develop more constructive outlets for social identity maintenance.