Why do so many Americans identify as working class and how does working class identity matter in American politics? This book argues that subjective working class identity, distinct from objective indicators like income, education, or occupation, is a consequential and underexamined force in U.S. politics and policy. Drawing on social identity theory, Franko and Witko show that identification with the working class shapes how people interpret their economic interests and navigate political choices, independent of their objective class position. par Against the conventional wisdom that America is uniquely a middle class society, and against claims that class has become obsolete in a post-industrial economy, the book demonstrates that working class identification remains widespread and politically meaningful. It traces how this identity varies across time and demographic groups, how it is shaped by broad economic transformations like rising inequality, stagnant mobility, and economic insecurity, and how it is actively constructed by political actors such as parties and unions. The book further shows that some economically secure, highly educated professionals paradoxically identify as working class, while some in objectively working class positions identify upward, complicating simple materialist accounts. par Situating class identity alongside racial, ethnic, gender, and religious identities, the authors show that working class identity exerts independent effects on policy attitudes, voting behavior, and broader political outcomes. The book offers a contemporary account of class politics in the United States.