During national emergencies, democratically elected leaders have sought to expand executive power in ways that violate democratic norms, ostensibly to guide their nation through crisis. Drawing from research on democratic backsliding, we anticipate support for such executive privileges may stem from different ideological and contextual factors, but primarily from inclinations toward ethno-nationalistic and authoritarian populism. We propose American Christian nationalism represent such inclinations. Analyses of nationally representative data reveal Christian nationalism is the strongest predictor Americans believe unspecified “national emergencies” might require leaders to suspend elections, suppress political opponents, and disregard checks and balances. However, political disinterest, stronger Democratic partisanship, and being Black (vs. White) are also positively associated with support for violating democratic norms, and these associations are amplified by Christian nationalism. Ancillary analyses suggest the interactions with race and party may be contextual, due to a Democratic President in office at the time of the survey. Findings suggest populist impulses characteristic of Christian nationalism may combine with political disinterest (perhaps reflecting disillusionment) and threats to in-group power to increase support for leaders suspending democratic norms during national crises.