I just finished this book by Thomas Holbrook (a fellow Iowa Ph.D.). I’m considering adopting it for my Parties, Campaigns, and Elections class in the fall.
This book starts by summarizing previous political science research that examines the extent to which campaigns “matter” in determining the ultimate outcome of presidential elections, especially in comparison with other more fundamental factors like international and economic conditions. The author then analyzes how public opinion changes in response to specific campaign events (debates, conventions, etc.) The final conclusion is that prevailing national conditions set the “parameters” within which campaign events exert smaller, but significant effects. So basically, the answer given by this book is yes, campaigns matter, but not as much as we often think they do. Economic and international factors matter more. However, the smaller effects of campaign events can be decisive in close elections.
Chapter 5 specifically looks at the effects of the presidential debates of 1984, 1988, and 1992 and finds that they exert an important effect, but less than that of nominating conventions. Also of interest to the Centre College community: the three vice-presidential debates barely moved the needle at all in terms of affecting the ultimate outcome of those three electoral contests. Hopefully the 2012 VP debate will defy this pattern!