n. A person who remains in close proximity to an important leader, particularly during photo sessions, to achieve increased media exposure.
The other little irony in the new order of British politics is the humourless similarity between new Labour and the bratpack that constitutes the new right. You can spot new Labour klingons from the first whiff of their Armani aftershave. They are not a great deal different from the Tory velcroids who have made their mark toiling at the coal face of financial services, or screaming abuse in a council chamber along the Thames estuary. What they both have in common is the blind pursuit of power: new Labour now, and the new right after defeat, when they will rally around John Redwood, Michael Portillo, or Imelda Marcos if she is available.
—Jerry Hayes, “Why I'm staying put,” New Statesman & Society, January 05, 1996
And if you've ever noticed a person who always seems to be hanging around someone more important during photo opportunities, that person is refered to in political circles as a ''velcroid.''

''It's someone who tries to enhance his own status by attaching himself to someone more important,'' said Soukhanov. ''James Baker was alleged to have been a velcroid.''
—Alan Dumas, “ (n),” Rocky Mountain News (Denver, CO), August 26, 1995
1991 (earliest)
White House photographers and advance men, accustomed to watching the maniacal maneuvering to get into the shot, have developed their own code language for masters of the art.

"Velcroids" are officials who form a Velcro-like attachment to President Bush at an event in Washington or on the road, sticking to him everywhere he goes in the hope of turning up next to him in newspapers or on television.

"Velcrosis" is the malady from which Velcroids suffer.

"Limo bait" is a time-honored trick used by local politicians when Mr. Bush visits their towns. A Velcroid will come up to Mr. Bush as he climbs into his limousine. He will begin telling the President something he needs to know about the scheduled event, hoping that Mr. Bush will invite him into the car to finish the conversation, since pictures taken with the President in his limousine are exceptionally prestigious trophies.
—Maureen Dowd, “Saving Face Means Having It in the Picture,” The New York Times, June 16, 1991