In recent years, students of voting behavior have become increasingly interested in valence politics models of electoral choice. These models share the core assumption that key issues in electoral politics typically are ones upon which there is a widespread public consensus on the goals of public policy. The present paper uses latent curve modeling procedures and data from a six-wave national panel survey of the American electorate to investigate the dynamic effects of voters’ concerns with the worsening economy -a valence issue par excellence- in the skein of causal forces at work in the 2008 presidential election campaign. As the campaign developed, the economy became the dominant issue. Although the massively negative public reaction to increasingly perilous economic conditions was not the only factor at work in 2008, dynamic multivariate analyses show that mounting worries about the economy played an important role in fueling Barack Obama’s successful run for the presidency.