Using a dataset of women state senators from all 50 states (1978–2010) and latent growth curve analysis, this article tests two longitudinal theories of the growth of women's political representation over time. Gender salience theory posits that women increase their political representation when they explicitly campaign on their gender. Political climate theory argues that women fare better electorally during periods when domestic issues predominate as opposed to international issues. Results provide support for gender salience theory, but the evidence is too mixed for political climate theory to provide a plausible explanation for the growth in women's state-level political representation. By political party, results suggest that Democratic women were generally advantaged over Republican women; however, Republican women exclusively benefited in the 1992 and 2010 elections. This article concludes with an assessment of the two longitudinal theories and what they may tell us more broadly about women in politics.