The perception of a home state advantage in presidential elections has been evident throughout American political history. Most presidential nominees have come from populous states with the potential to deliver many electoral votes (Adkison 1982). (1) Likewise, party leaders and presidential nominees have tended to select vice presidential running mates from large states (Sigelman and Wahlbeck 1997), although seemingly less so in recent decades (Hiller and Kriner 2008; see also Baumgarmer 2008). Today, the prospect of a home state advantage influences popular discussion of vice presidential selection and even presidential campaign strategy (see Devine and Kopko 2011).
The perception of a home state advantage was not subjected to systematic empirical analysis, however, until the 1970s and 1980s, when political scientists began studying its strength and causes. The home state advantage literature today boasts many theoretical, methodological, and empirical advances. Yet it also has important limitations that we seek to address in this article.
First, most studies of the home state advantage analyze presidential or vice presidential candidacies, but not both. (2) In this article, we provide the most comprehensive comparison of presidential and vice presidential home state advantage to date. We analyze and compare the strength and causes of presidential versus vice presidential home state advantage, using identical empirical measures and methodologies that are consistent with the leading works in that literature. Most fundamentally, we attempt to document and explain the differential strength of presidential and vice presidential home state advantages. Based upon the discrepant power of their offices and recent studies of interaction effects on the vice presidential home state advantage, we expect vice presidential advantages to be rather small and highly conditional, in contrast to relatively large and universal presidential advantages. If this is so, our analysis will help to guide expectations for whether and when to expect substantial presidential and/or vice presidential home state advantages. Also, this analysis will contribute to scholars' understanding of voting behavior in presidential elections, particularly in terms of the weight given to presidential versus vice presidential characteristics.
Second, previous studies of home state advantage have not explored the process by which a home state advantage occurs. In this article, we seek to identify patterns in state voting behavior that could help to explain the occurrence and size of a home state advantage. Vote choice, after all, is the product of numerous influences, most notably party identification and candidate attributes (Campbell et al. 1960; Lewis-Beck et al. 2008). Given the abundance of alternative motivations, the decision to vote on a home state basis is actually quite remarkable and surely limited to a relatively small subset of the state electorate. Previous studies of the home state advantage, however, offer little insight into the characteristics or behavioral patterns of those individuals who provide a home state advantage.
Home state advantage could be attributable to various aggregate behavioral patterns. We propose the following explanations: disproportionate partisan conversion among the previously existing state electorate, disproportionate partisan mobilization of previous nonvoters, or a combination thereof. (3) This conceptualization closely mirrors a major debate in the partisan realignment literature about whether critical elections and subsequent realignments are best explained by conversion among existing voters or mobilization among previous nonvoters. We draw upon this literature to interpret the process by which home state advantages occur.
Our analysis of that process begins by measuring the effect of home state candidacy on home state turnout. After analyzing presidential versus vice presidential home state turnout advantage, we incorporate a turnout variable into empirical models predicting the size of home state electoral advantages. The effect of home state turnout on home state advantage can be conceptualized as a continuum, where at one extreme mobilization completely explains home state advantage, and at the other extreme, conversion completely explains it. Between these extremes lies a combination of the two effects, whereby home state advantage is to some degree the product of voter mobilization and voter conversion. We seek to determine whether home state advantages are primarily attributable to mobilization or conversion. This inquiry represents an important new dimension in the home state advantage literature, advancing beyond questions of when and to what extent advantages occur to questions of how they take shape. (4)
Lewis-Beck and Rice (1983) grounded their foundational study of the presidential home state advantage in V. O. Key's "friends and neighbors" hypothesis. According to Key (1949), candidates for elected office should perform best among voters living in close geographic proximity to them. Key provided four reasons for this advantage; local voters are most likely to (1) be familiar with the candidate and his/her political qualifications and views; (2) come into personal contact with the candidate's staff, associates, or even the candidate him/herself; (3) view the candidate as knowledgeable about local concerns and inclined to direct government resources toward addressing them; (4) share a common sense of geographic identity and therefore see the candidate as "one of our own."
Originally, Key's conception of the friends and neighbors hypothesis was exclusive to elections at the state and substate level. (5) He did not believe the hypothesis had any applicability to the home state advantage in presidential elections because "states gradually have become more alike in the manner of their presidential voting" (Key 1956, 26-27). Lewis-Beck and Rice (1983) rejected Key's line of argument while adopting his theory. Loyalty to a home state presidential candidate, they argued, "is not wholly unreasonable" because in such situations "We are offered the psychological satisfaction of identification with a president who is more like our 'friends and neighbors.' Further, we might hope that as president he would remember the 'folks back home' when distributing federal largess." At a more sentimental level, "It gives us a chance to show 'pride in our own' by voting for a native son" (Lewis-Beck and Rice 1983, 552).
Lewis-Beck and Rice also contributed to this line of research by conceptualizing the home state advantage in terms of "how many votes [the presidential candidate] got [in his home state] beyond what was expected" (1983, 549). They measured home state advantage as the difference between a home state's deviation from past partisan voting trends and the nation's deviation from the same. The formal equation is
H = ([S.sub.a] - [S.sub.e]) - ([N.sub.a] - [N.sub.e])
where H is the presidential candidate's estimated home state advantage in a given election; [S.sub.a] is the vote percentage won by the presidential candidate in his or her home state in a given election; [S.sub.e] is the average vote percentage won by the presidential candidate's party in his or her home state over the five most recent presidential elections; [N.sub.a] is the vote percentage won by the presidential candidate nationally in a given election; and [N.sub.e] is the average vote percentage won by the presidential candidate's party nationally over the five most recent elections. (6)
Lewis-Beck and Rice estimated the average presidential home state advantage in the 1884-1980 elections to be 4.0%, and statistically distinguishable from zero. Next, they regressed the home state advantage on three predictors, all of which were statistically significant: home state population, presidential incumbency, and the party of the presidential candidate. Of the three predictors, population is the most theoretically interesting; reflecting upon Key's four reasons for expecting a friends and neighbors effect, Lewis-Beck and Rice argued that "All of the aforementioned conditions for strong local bonds are maximized in small states" (1983, 552). (7)
Lewis-Beck and Rice's work soon inspired similar analysis of the vice presidential home state advantage. Dudley and Rapoport (1989) adopted, with minor revision, Lewis-Beck and Rice's home state advantage equation to study vice presidential candidacies in the 1884-1984 presidential elections. "Such an extension," they argued quite reasonably, "seems particularly warranted since the vice-presidential candidate is one political nomination still made by party elites who can purposely take regional appeals into account" (Dudley and Rapoport 1989, 537). (8)
Dudley and Rapoport estimated the average vice presidential home state advantage to be only 0.3%, and not statistically different from zero. Using the same methods as Dudley and Rapoport and a data set updated to include elections through 2008, Devine and Kopko (2011) have since estimated the average vice presidential advantage to be slightly higher, at 0.69%, but still not statistically significant.
Although Dudley and Rapoport, as well as Devine and Kopko, did not estimate the presidential home state advantage in these studies, their data and methods so mirror those of Lewis-Beck and Rice that it would seem vice presidential candidates attract smaller home state advantages than presidential candidates. The reason for this discrepancy is likely due to significant differences in presidential versus vice presidential candidacies: Presidential candidates are far more visible on the campaign trail and more powerful once in office than their vice presidential running mates; therefore, voters should be more influenced by characteristics of the presidential candidate than those of the vice presidential candidate, whether geographic or...