Realignment: The Theory that Changed the Way We Think About American Politics tells the dramatic story of how a new approach to American politics emerged in the afternmath of Harry Truman's stunning 1948 election upset victory. This approach—realignment theory—held that critical elections such as those of the Civil War era, the 1890's, and the 1930's shaped politics for decades to come. Theodore Rosenof details how realignment theory emerged as the predominant explanation of electoral change and how, after decades of analysis, it remains a subject of continuing influence and controversy. The first history of this important theory, Realignment weaves history and political science into a compelling look at American elections.