In recent years the welter of data accumulated on American voting behavior has been continually reanalyzed by social scientists interested in building theories of electoral choice. Most of the original data-gathering enterprises were guided by general theoretical frameworks which, for the most part, were not developed to a point where the ensuing analyses addressed themselves unambiguously to the overall conceptions by which they were guided. As a result much of our knowledge about voting behavior is in the form of generalizations about what social and psychological variables account for voting choices while we lack conceptual frameworks which systematically interrelate these generalizations and provide comprehensive and parsimonious explanation. If any one unifying conception has emerged from the original large scale studies it is that the average voter is irrational. This inference has been derived from a variety of empirical relationships coupled with varying conceptions of rationality.The more recent reanalyses of these data sets have been characterized by a theoretical sophistication that was lacking heretofore. One of these, a theory of the calculus of voting, has applied some formal rigor to the question of the rationality of the decision to vote, selected empirical equivalents of theoretical entities from survey data on national elections, and conducted a successful test of the theory. Unlike traditional approaches to the rationality question which infer the degree of rationality from quantities of information possessed or from correlates of decisions (background, party affiliation, group memberships, etc.), this investigation conceived of rationality in terms of the kind of calculus employed by the individual in deciding among alternatives (in this case whether or not to vote).