I remember reading a book about how Vegas sets the football line. Early on Sunday night they take their best guess on what it will take to get the even split Mayor mentioned. Then they release the line to a select group of professional gamblers who bet into the line which is adjusted until the bets are pretty much 50/50. I think the book was written way back in 1973 called the The National Football Lottery. According to Amazon you can pick up a used copy for a penny. Must not have helped the seller too much.
