His research and teaching deal primarily with the United States in the long twentieth century, with emphasis on the intersections of religion, politics, and economics, and the rising influence of the American West and Sunbelt Southwest in national life. His first book, From Bible Belt to Sunbelt: Plain-Folk Religion, Grassroots Politics, and the Rise of Evangelical Conservatism (2011), won the American Historical Association's John H. Dunning Prize and the OAH Ellis W. Hawley Prize. He is also a coeditor of Sunbelt Rising: The Politics of Space, Place, and Region (2011), and Faith in the New Millennium: The Future of Religion and American Politics (2016). His current book project, tentatively titled "Anointed With Oil: God and Black Gold in America's Century," is a study of religion and politics in North America's age of oil, 1890 to the present.