The Daisy Girl was was a TV ad that ran in September 7, 1964. This ad showed a girl with a daisy, who is then replaced by a gigantic nuclear blast. The ad was designed to damage the reputation of candidate Goldwater.
Although Goldwater was not mentioned by name, viewers understood the reference. Goldwater had voted against the nuclear test ban treaty. The ad referenced this by showing how destructive and damaging nuclear tests are, and linking this destruction with Goldwater's interest in continuing them. The ad was particularly successful because it appealed to the feelings of the viewers, not their reason.