This study uses a unique experimental design to examine the ways in which gendered messages about the sources of women’s underrepresentation in politics influence their levels of political interest, knowledge, and efficacy. We test two forms of such messages: supply-side arguments that attribute women’s underrepresentation to their lack of interest, and demand-side arguments that attribute women’s underrepresentation to institutional discrimination. We find that framing women’s political underrepresentation as a question of institutional demand – in other words that external, structural barriers cause women’s unequal representation – promotes positive psychological orientations to politics, in part because it disrupts dominant narratives about women in politics.