David Ogilvy was a highly successful advertising executive, often called "The Father of Advertising" and he created several iconic advertising campaigns. However, his IQ was very average:

Including intelligence, said he. They both took an IQ test he found in the back of a book. He got a 96 (“par for ditch diggers”), and she (his wife, Herta Lans) got 136. It changed their relationship. “Suddenly she’s pretty and clever and I’m ugly and dumb.”

source: The King of Madison Avenue: David Ogilvy and the Making of Modern Advertising

So if you're actually interested, you could look into his life.