on the bandwagon, get

on the bandwagon, get

Also, climb or hop or jump on the bandwagon . Join a cause or movement, as in More and more people are getting on the bandwagon to denounce cigarette smoking. This expression alludes to a horse-drawn wagon carrying a brass band, used to accompany candidates on campaign tours in the second half of the 1800s. By about 1900 it was extended to supporting a campaign or other cause.
See also: get, on