Horace Wilcox was the former congressman of Springfield and member of the Springfield Republican Party.
The Simpson family went to see him about the planes going over their house, as the noise made it impossible to sleep, or do other things. He had agreed to help, but died of a heart attack before he could do anything. With no one to turn to, the Simpsons decided to get Krusty to replace Wilcox as congressman.
According to Kent Brockman, Wilcox was a Titanic survivor; since the ship sunk in 1912, Wilcox would have been at least 91 years old when he died.