My thanks to John for the following info on the "Bandwagon:"
One of the more frequent questions to this site's discussion forum has been where the phrase jump on the bandwagon comes from. The confusion stems from the fact that the phrase survives into the 21st century while bandwagons are long gone.
In 19th and early 20th century America, a bandwagon was exactly what it sounds like, a wagon, usually horse-drawn, which carried a musical band. Bandwagons were used in circuses, to lead parades, and at political rallies. Hence to join or jump on the bandwagon was to follow the crowd, and in a political context with the connotation that one was there for the entertainment and excitement of the event, rather than from deep or firm conviction.
The first known use of the term bandwagon is from 1855 in P.T. Barnum's Life:
At Vicksburg we sold all our land conveyances excepting four horses and the "band wagon." Use of a bandwagon as a metaphor for a political campaign dates to at least 1884, when the magazine Puck published a cartoon depicting Chester A. Arthur driving a bandwagon full of presidential hopefuls.
The familiar phrase first appears in an 1899 letter by Theodore Roosevelt:
When I once became sure of one majority they rumbled over each other to get aboard the band wagon.
(Updated: 20 June 2003; Sources: Oxford English Dictionary, 2nd Edition and Safire's New Political Dictionary.)