If you've got cable TV, Sundance Channel is running the Tanner '88 miniseries. It's a faux documentary of a fictional candidate running in the 1988 primaries, with footage of the real candidates running that year thrown in.
It's a good and entertaining look at the process. And it's directed by the great Robert Altman and written by Doonesbury's Gary Trudeau, so you're in good filmmaking hands.
They're airing every Tuesday evening, with repeats through the week. Worth checking out.