This book is an extended argument about how people form political preferences. It seeks to show how news and political arguments diffuse through large populations, how individuals evaluate this information in light of their political values and other predispositions, and how they convert their reactions into attitude reports on mass surveys and vote decisions in elections.

The argument of the book applies to a very wide range of problems in mass political behavior – among them, racial and political tolerance, support for American involvement in overseas wars, voting in presidential and congressional elections and in presidential primaries, presidential popularity, trust in government, and judgments about the economy.

The dynamic element in the argument – the moving part, so to speak – is coverage of public affairs information in the mass media. This coverage may consist of ostensibly objective news reports, partisan argumentation, televised news conferences, or even paid advertisements, as in election campaigns. What matters for the formation of mass opinion is the relative balance and overall amount of media attention to contending political positions.

Although the book deals with the formation of political preferences in numerous cases, it maintains a high level of generality. The aim is to integrate as much as possible of the dynamics of public opinion within a cohesive theoretical system.