Competition and the Dynamics of Issue Convergence

Issue convergence theory suggests that candidates should respond to their opponents by discussing the same issues whereas issue divergence theory posits that candidates should instead ignore each other and discuss different issues. Recent studies tend to find evidence in favor of issue convergence, but these results may be inaccurate because the analyses that generated them tested dynamic campaign behavior using cross-sectional methods. Using a dynamic modeling strategy along with television advertising data drawn from 93 U.S. Senate campaigns in 44 states, 5 election years, and on 51 issues, I show that candidates increase the attention they devote to issues as their opponents' emphasis of these same issues increases and that candidates do so to a greater extent in competitive than in noncompetitive elections. This analysis is the first to account for the dynamic nature of issue emphasis and provides support for issue convergence theory.