This volume provides the most systematic study on the role of religion and religiosity in electoral politics in Catholic, Protestant, and religiously mixed countries across Western Europe and in the United States, from the Second World War until the second decade of the new century. The volume’s main argument is that, despite the expectations of secularization theory, religiosity remains relevant when casting votes. The book pleads the case for the substituting of the notion of religious-cleavage voting with the concept of religious voting. First, it provides a thorough conceptual analysis of the historical circumstances under which religious-cleavage voting has developed, by distinguishing it from the notion of religious-coalescence voting. Then it discusses the adequacy of the religious voting paradigm to explain the resilience of religion and religiosity in Western Europe and the United States of America from the 1980s to the present day in a context of mass secularization. Expectations are tested through fifteen single-country longitudinal analyses based on the National Election Studies data and cross-country comparisons based on various datasets such as European Values Studies (EVS), European Social Surveys (ESS), and European Election Studies (EES). Results show that variations in religious voting are strictly conditional on the agency of various actors, political and social, and to the previous as well as contemporary conflicts about religious or moral issues. Contributors to the volume are all renowned specialists in the field of electoral politics and comparative voting behaviour.