I'm not even American and even I know of School House Rock's "Just a Bill" and the Simpson's parody "An ammendment to be". In Just a Bill the bill is written by a congressman because of public outcry.
I was watching a TV program, called "Why Poverty", which said the idea of a congressman writing a bill was antiquated and that now-a-days bills were writen exclusively by lobby groups. The idea was that when you're rich enough you can buy a lobby group to make laws for you, basically destorying the idea of democracy. Here's an another Just a bill parody, this one supports the idea that lobby groups write bills.
Who actually writes congressional bills in America? To be specific lets say over the last 10 or 20 years, answerers choice.