All the King's Men by Robert Penn Warren
Robert Penn Warren's All the King's Men is generally considered the finest novel ever written on American politics. Set in the 1930s and first published in 1946, it traces the rise and fall of Willie Stark who began his political career as an idealistic man of the people, but soon fell prey to the corruption of success. Steven Zaillian's (Schindler's List) adaptation of All the King's Men, featuring an all-star cast led by Sean Penn, Jude Law, Kate Winslet, Patricia Clarkson, James Gandolfini, Mark Ruffalo, and Anthony Hopkins (Columbia Pictures) is scheduled for release in late 2005/early 2006.