Which scenario best represents realignment?

Realignment refers to a significant and lasting shift in the electoral base of political parties, often marked by changes in voter preferences and party allegiance. The scenario where voters shift their preferences from one major party to another best captures this concept. Such shifts often occur in response to major social, economic, or political changes, leading to a new balance of power in the electorate.

In this context, when voters actively change their support from one party to another—such as from the Democratic Party to the Republican Party or vice versa—it signifies a realignment in the political landscape. This change can result in new electoral coalitions forming and can influence policy agendas and party platforms for years to come.

Realignment typically does not occur simply because a third party wins an election, which is more reflective of a short-term electoral success rather than a fundamental shift in party support. Similarly, increases in voter turnout might indicate greater engagement but do not inherently signify a change in party allegiance. Likewise, consistent party loyalty over generations represents stability in the political system rather than the dynamic change characteristic of realignment. Thus, the second scenario exemplifies realignment by showcasing the movement of voter preferences between the established major parties.