The US Republican presidential candidate Newt Gingrich and his wife Callista were hit with glittery confetti by a protester during the couple's appearance at a book-signing in Minneapolis on Tuesday.
The man approached the Gingriches during the signing at a downtown hotel.
As Gingrich handed him a signed copy of the book, the protester dumped a cracker box full of confetti on the pair, shouting: "Feel the rainbow, Newt! Stop the hate! Stop anti-gay politics! It's dividing our country and it's not fixing our economy!"
The man was quickly pushed out of the room by an event organiser.
Although authorities couldn't immediately confirm the man's identity, he appeared to be Nick Espinosa, an event crasher who disrupted at least two other political events in Minnesota, including one in which he dumped a bagful of pennies in the lap of a Republican candidate for governor last year.
In that prank, Espinosa - who has also used the name Robert Erickson - told reporters he was trying to highlight immigration issues.
Espinosa emailed reporters later on Tuesday and attached pictures of the confetti attack.
He said it was a protest against a proposal to amend Minnesota's constitution to ban gay marriage.
