Part of the reason incumbents are so successful at reelection is that they scare off potential challengers.

Question

Quizplus · Accepted Answer

Incumbents have the advantage of name recognition, established relationships with donors and supporters, and access to resources that make them difficult to defeat. Additionally, incumbents may use their position to intimidate potential challengers by implying that they will use their power to make the challenger's life difficult if they run against them. This can lead to a lack of competition in elections and ensure easy re-election for the incumbent.

Part of the Reason Incumbents Are So Successful at Reelection