Turn on the television or sign in to social media during election season and chances are you’ll see plenty of negative campaigning. For decades, conventional wisdom has held that Americans hate negativity in political advertising, and some have even argued that its pervasiveness in recent seasons has helped to drive down voter turnout. Arguing against this commonly held view, Kyle Mattes and David P. Redlawsk show not only that some negativity is accepted by voters as part of the political process, but that negative advertising is necessary to convey valuable information that would not otherwise be revealed.

The most comprehensive treatment of negative campaigning to date, The Positive Case for Negative Campaigning uses models, surveys, and experiments to show that much of the seeming dislike of negative campaigning can be explained by the way survey questions have been worded. By failing to distinguish between baseless and credible attacks, surveys fail to capture differences in voters’ receptivity. Voters’ responses, the authors argue, vary greatly and can be better explained by the content and believability of the ads than by whether the ads are negative. Mattes and Redlawsk continue on to establish how voters make use of negative information and why it is necessary. Many voters are politically naïve and unlikely to make inferences about candidates’ positions or traits, so the ability of candidates to go on the attack and focus explicitly on information that would not otherwise be available is crucial to voter education.

If Barack Obama had not won in Iowa, most commentators believe that he would not have been able to go on to capture the Democratic nomination for president. Why Iowa? offers the definitive account of those early weeks of the campaign season: from how the Iowa caucuses work and what motivates the candidates’ campaigns, to participation and turnout, as well as the lingering effects that the campaigning had on Iowa voters. Demonstrating how “what happens in Iowa” truly reverberates throughout the country, five-time Iowa precinct caucus chair David P. Redlawsk and his coauthors take us on an inside tour of one of the most media-saturated and speculated-about campaign events in American politics.

Considering whether a sequential primary system, in which early, smaller states such as Iowa and New Hampshire have such a tremendous impact is fair or beneficial to the country as a whole, the authors here demonstrate that not only is the impact warranted, but it also reveals a great deal about informational elements of the campaigns. Contrary to conventional wisdom, this sequential system does confer huge benefits on the nominating process while Iowa’s particularly well-designed caucus system—extensively explored here for the first time—brings candidates’ arguments, strengths, and weaknesses into the open and under the media’s lens.