Critical realignment refers to a significant and lasting shift in the political landscape, often characterized by changes in party affiliation, voter behavior, and electoral outcomes. This phenomenon typically occurs during periods of social upheaval or major political events, leading to the reorganization of political coalitions and the emergence of new dominant parties. Historically, critical realignments have reshaped the United States political system, such as the transition from the Democratic dominance of the 1930s to the Republican ascendancy in the 1980s. These shifts can redefine the priorities and policies of political parties, influencing governance and public policy for decades.