The study of elections in political science has long benefited from scholars who bring a theoretical focus on geographic processes and who employ the tools of spatial analysis. Barney Warf and Jonathan Leib's edited volume integrates several recent compelling studies using these diverse approaches to electoral geography. Collectively, these studies, by examining electoral systems from across the world, illustrate how: 1) the analysis of election outcomes is enhanced by considered place-based factors, and 2) the geographic distribution of social, economic, and political institutions structures the geography of voter preferences and behavior.

The authors of this volume thus confront a fundamental question for political geographers: How do the tools and analytical perspectives of political geography complement and build upon the existing methodological tools and frameworks already found in political science? One possibility is that electoral geographers simply enhance existing studies of voter behavior by accounting for the local geographic context and the local political institutions that shape elections. But a second, richer answer is that electoral geography offers theoretical explanations for the processes that shape how voters and political institutions are distributed across geographic space; in turn, the interaction of these voters and institutions across space produces surprising political outcomes that would have been overlooked without considering geography.

This second answer offers the most fruitful opportunities for the subfield of electoral geography within political science and also describes the most valuable contributions of this edited volume. The subfield has successfully moved beyond merely treating geography as a nuisance variable, thus allowing for the development of unique, substantive insights regarding the roles of income, identity, and electoral institutions in politics.

An important example is the chapter by Daniel McGowin, which carefully explains how the distinct, geographically segregated distribution of voters in recent Taiwan elections is the product of several spatial-based phenomena. These phenomena include the infiltration of Chinese mainlanders in northern Taiwan, the opposition voters in the south who were galvanized by their proximity to the Kaohsiung Incident, and the geographic concentration of agricultural laborers in the east.

The strength of McGowin's work is its qualitative explanation of the historical processes by which voters came to be geographically clustered across regions. Such explanations, in turn, allow for political scientists to understand the microfoundations of voter behavior with much greater depth, going beyond the traditional answers that draw upon conventional socioeconomic, demographic, and religious explanations of voting.

Of course, a potential danger of such rich, detailed explanations of electoral geography is that they may lack generalizability beyond the immediate case at hand. The challenge, then, is for political geographers to offer theoretical answers that have applicability beyond a single country or state, while nevertheless being careful to account not merely for geographic factors but also for reasons why voters are geographically distributed as they are.

The chapter by Fred Shelley and Heather Hollen presents compelling opportunities for electoral geographers to meet this challenge. Shelley and Hollen illustrate that a voter's geographic residence strongly predicts not only that voter's partisan preferences but also his or her specific candidates preferred within each party. Analyzing US primary election data from the 2008 presidential campaign, the authors find that among Democratic voters, rural, poorer individuals preferred Hillary Clinton, while urban and upscale voters supported Barack Obama. A comparable pattern emerges for Republicans, among whom rural voters supported Mike Huckabee, and urban, wealthier voters preferred John McCain.

Why are these primary voting patterns theoretically significant? First, they suggest that the relationship between voters' residential patterns and their political preferences may be richer and more complex than the simple left–right political spectrum that is traditionally associated with the urban–rural geographic dimension. Political scientists have long noted that left-wing voters tend to be geographically concentrated in urban constituencies, hence leaving rural and suburban districts to be relatively more right wing. Shelley and Hollen's chapter builds upon and expands this classic understanding of voter geography by highlighting the important geographic diversity of voters within each political party. The findings suggest, for example, that rural Democrats have different motivations than urban Democrats for their shared partisan preferences, and these divergent motivations may reflect economic, social, religious, and historical differences between rural and urban Democrats.

Second, the authors' findings have implications for turnout differences between rural and urban areas. If voters within a single party are stratified along geographic lines, and primary elections create winners and losers within each party, then fluctuations in general voter turnout are driven by more than traditionally hypothesized factors, such as demographics and economic malaise. Instead, Shelley and Hollen's findings suggest that the geography of primary election voting patterns could explain why rural voters may have had less motivation to participate in the general election than did urban voters. While the 2008 general election is commonly recognized as a short-term spike in voter turnout, this heightened voter participation was not geographically uniform, and the authors' findings offer a possible explanation for such clustered behavior.

Shelley and Hollen stop short, however, of offering a systematic explanation of rural voters' preferences for Clinton and Huckabee and urbanites' support for Obama and McCain. They cite numerous characteristics of rural Democrats and Republicans that may have been relevant in their candidate preferences but leave a more extensive analysis of these factors for future work. Hence, their contribution to our understanding of voting behavior, while intriguing, still possesses untapped potential. It is to be hoped that future analysis will continue to explore more fully the differences between rural and urban voters and how they arrive at their candidate preferences.

Such an exploration comes in Warf's chapter on the geographic patterns of voter preferences in the November 2008 McCain–Obama election. Analyzing how the socioeconomic, ethnic, and religious predictors of presidential vote choice vary across geographic space, Warf attempts to explain not simply how geography matters but also why it matters in models of electoral behavior. Specifically, he finds that after accounting for voters' income and racial and religious identity, voters were most likely to choose Obama “in regions in which supporters were a relative minority” (p. 152). Hence, for example, among the national set of black voters, those residing outside of the Deep South, where blacks are relatively well represented, exhibited the highest support for Obama.

Why should being a socioeconomic, ethnic, or religious minority relative to the surrounding region affect one's vote choice? Warf argues that being such a region-based minority may cause voters to be “more sympathetic to a candidate who was a member of an ethnic minority himself” (p. 152). By this explanation, it is not merely one's own identity that affects vote choice. Instead, the similarity of one's identity to that of geographically proximate individuals also determines how much a voter sympathizes with a minority candidate.

Such provocative and theoretically rich arguments are the sort that will allow electoral geographers to claim unique substantive contributions to the study of voter behavior. This edited volume introduces political scientists to compelling work, with the potential for progress beyond the electoral geographers of previous generations. In important ways, the various authors of this volume go beyond merely describing and identifying the geographic factors that matter in elections. Instead, they begin to explain the geographic processes that originally caused spatial patterns in voters and institutions to arise. It is these theoretically rich explanations that make Revitalizing Electoral Geography compelling.