Median Voter Theory (MVT) suggests that in a majority-rule election, the candidate closest to the median voter’s views will win. Since most voters are partisan and vote predictably, elections are decided by swing voters in the middle. To win, candidates adjust their positions to attract this decisive group, often moving toward the political center.

Developed by Anthony Downs in 1957, MVT explains why general election candidates tend to sound more moderate than during primaries, where they appeal to their base. Over time, this leads to policy convergence, with major parties offering similar centrist policies.

However, MVT assumes politics follows a single left-right spectrum, ignores low voter turnout, and struggles in polarized environments, where candidates may focus more on energizing their base than winning the middle. Despite these flaws, MVT remains a key theory in understanding why democratic elections often favor centrist policies over extreme positions.

From ChatGPT.