Political realignment

A realigning election (often called a critical election, political realignment, or critical realignment) is a term from political science and political history describing a dramatic change in the political system. Scholars frequently apply the term to American elections and occasionally to other countries. Usually it means the coming to power for several decades of a new coalition, replacing an old dominant coalition of the other party as in 1896 when the Republican Party (GOP) became dominant, or 1932 when the Democratic Party became dominant. More specifically, it refers to American national elections in which there are sharp changes in issues, party leaders, the regional and demographic bases of power of the two parties, and structure or rules of the political system (such as voter eligibility or financing), resulting in a new political power structure that lasts for decades.

Realigning elections typically separate (what are known in the field of comparative politics as) Party Systems—with 1828, for example, separating the First Party System and the Second Party System in the U.S.

Political realignments can be sudden (1–4 years) or can take place more gradually (5–20 years). Most often, however, particularly in V. O. Key, Jr.'s (1955) original hypothesis, it is a single "critical election" that marks a realignment. By contrast a gradual process is called a "secular realignment." An American example was the change in the voting patterns among white Southerners, who from the 1870s to 1962 had overwhelmingly voted at the national and state levels for Democrats (what was called the "Solid South"). A critical election came in 1964 with a shift at the presidential level to the Republican (GOP) presidential candidates. However, there was a gradual shift toward the GOP at the state and local levels, as Aldrich (2000) and others have found. Democratic voting remained strong into the 1970s and only slowly shifted towards the GOP as state Republican organizations systematically broadened their base in the 1980s and 1990s.

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