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Gabriel Lopez-Moctezuma - Money and Votes in Electoral Competition: Evidence from the US Senate

Encina Hall West, room 400

Elections aggregate the preferences of voters into a collective decision. Before any vote is cast, though, the preferences of a different group of people come into play. Modern political campaigns need money to mobilize support, pay for political advertising, and fund ground operations. Since political campaigns in the US are primarily financed by voluntary individual political contributions, the preferences and decisions of individual contributors become central to the democratic process. We use a rich dataset on the choices and individual characteristics of millions of potential donors to quantify how ideological and non-ideological candidates’ characteristics affect donors’ preferences and behavior, and to understand how donors’ preferences shape electoral competition. For this purpose, we first recover measures of policy positions for incumbents and challengers scaling the corpus of candidates’ public statements during the campaign trail.  Second, we disentangle donor and voter preferences for ideology and valence by combining the variation in donors’  individual characteristics and choices with aggregate electoral returns. In particular, we model candidates as bundles of characteristics, including exogenous observable valence (e.g., gender, education), unobserved valence (e.g., skill, charisma), campaign spending and position taking (both considered endogenous, and possibly correlated with observed and unobserved candidate characteristics). Finally, we quantify the indirect effect of contributions on politicians’ policy choices by estimating a model of electoral competition in which candidates’ policy positions affect both voters’ preferences as well as campaign spending via the supply of individual contributions.  Overall, our analysis allows us to quantify how well voters are represented by politicians relative to contributors.


Gabriel Lopez-Moctezuma is an Assistant Professor of Political Science in the Division of the Humanities and Social Sciences at the California Institute of Technology. Previously, he was a Post-Doctoral Associate in the Cowles Foundation for Research in Economics at Yale University. He holds a Ph.D. in Politics from Princeton University where he was part of the Research Program in Political Economy and received the Charlotte Elizabeth Procter Fellowship.

His research analyzes collective decision-making in committees and elections using different quantitative methods, such as structural estimation, causal inference, and text analysis. He studies the effects of sequential decision-making at the Federal Open Market Committee (FOMC) and the U.S. Supreme Court. His research also focuses on electoral competition and voting behavior in the U.S., Mexico and the Philippines.