The BBC miniseries "State of Play" was great. The American film wasn't that bad either.
I'm intrigued by the Clooney/Gosling film THE IDES OF MARCH, based off of the play "Farragut North" written by a former Dean '04 staffer . . .
http://en.wikipedia.org/wiki/The_Ides_of_March_(film)
The problem is that it's so easy for films and television shows about politics to become cliched. See: later seasons of "The West Wing."
I might as well mention my favorite show "Mad Men." It's not a show about politics but it features it quite a bit. The principles of marketing and politics aren't that far apart anyway.