Bringing Converse Back In: Modeling Information Flow in Political Campaigns

In his 1962 paper, \"Information Flow and the Stability of Partisan Attitudes,\" Converse explained why moderately sophisticated voters are sometimes most susceptible to persuasion in election campaigns. Such people, Converse argued, pay enough attention to campaigns to be fairly heavily exposed to persuasive messages but lack the sophistication to be able to resist. The present article extends this model in several ways, showing that it can yield important insights into House elections, presidential elections, presidential primary elections, and the dynamics of presidential popularity. On the theoretical side, this article introduces the notion of differential information flow, which is the idea that campaigns consist of multiple messages that may penetrate differentially far into the mass electorate. It shows that differential information flow can help explain nonobvious but theoretically interesting patterns of attitude change in several areas. On the substantive side, this article pays particular attention to the dynamics of incumbent advantage in House elections, showing among other things, why senior incumbents are typically able to build up huge winning margins in weakly contested elections but are unable to maintain this advantage under challenge.