Discussion Networks, Campaign Momentum Swings, and Voting Behavior in Brazil and Mexico

• In Event: Elections and Voting Behavior in Latin America

Abstract

Many election campaigns in Latin America feature dramatic momentum swings, in which a candidate surges or decline in the polls. These surges are often meaningful, leading to a front-runner’s eventual demise or bringing an also-ran into contention. For example, a last-minute surge led to Felipe Calderon’s controversial victory over Andrés Manuel López Obrador in Mexico 2006. Why do these momentum shifts occur? The standard answer is that they occur as individuals are exposed to new candidate information, such as a gaffe or a negative advertisement, via the mass media. By contrast, I argue that the media only triggers momentum runs by initially publicizing these events. The main mechanisms for spreading this information are the social networks in which citizens have informal conversations about politics. Through these networks, politically colored information diffuses through the population, spreading just like other new ideas and innovations. I demonstrate this with unique panel survey datasets conducted during the 2002 and 2014 campaigns in Brazil and the 2006 campaign in Mexico. These datasets contain rarely measured aspects of respondents’ social networks along with measures of media exposure and vote choice.

Author

• Andy B Baker, University of Colorado/Boulder