climb on the bandwagon

To join, follow, or support someone or something only after they or it is successful or popular. I can't stand these people who just climb on the bandwagon after a win. Where were they last year when the team was terrible? A: "I thought your Mom hated that candidate." B: "Well, he's the president now, so she's climbed on the bandwagon." Please, you just climb on the bandwagon whenever the team is in the playoffs. Can you even name five players on the active roster?

climb/jump on the ˈbandwagon

(informal, disapproving) do something that others are already doing because it is successful or fashionable: As soon as their policies became popular, all the other parties started to climb on the bandwagon.At political celebrations in the USA, there was often a band on a large decorated vehicle (= a bandwagon). If somebody joined a particular ‘bandwagon’, they publicly supported that politician in order to benefit from their success.

on the bandwagon, to get/climb/hop

To join the cause, movement, or party. The original bandwagon was a horse-drawn wagon bearing a brass band, used in a circus parade. In the second half of the nineteenth century such wagons began to be used in political campaigns as well, accompanying a candidate on speech-making tours. During William Jennings Bryan’s presidential campaign of 1900 the term began to be extended to mean supporting the movement itself. It also was used in Britain: “The Mirror . . . does not jump on bandwagons . . . it isn’t, never has been, and never will be a tin can tied to a political party’s tail” (Daily Mirror, 1966; cited by William Safire).