Moments of mass mobilization astound us. As a sea of protesters fills the streets, observers scramble to understand this extraordinary political act by ‘ordinary’ citizens. This study presents a paired comparison of two ‘moments’ of mass mobilization, in Ukraine and Argentina. The two cases are compared and analyzed on a cross-temporal and an inter-regional basis, thereby offering two critical cases in response to assumptions that the processes and patterns of mobilization, and democratization politics more broadly, are region specific. This study challenges political science’s focus on elites and structural factors in the study of political participation during democratization.