The sole redeeming feature of this movie lies in the fact that it attempts to illustrate how corrupt our elected officials can be. It should come as no surprise by now that the characters in the movie have a resemblance to Bill and Hillary Clinton and their 1992 Presidential campaign co-workers. In retrospect, it's easy to see how a movie about such a campaign can make for one of the most boring plots ever. I personally find hard to work up an interest in the real world for any election. This is particularly distracting because the outcome here is far more certain than the 1996 U.S. Presidential elections.
Loose threads are aplenty.
For example, relationships that appear key to the plot device are never explored. Resolution of scandals, when it occurs, are quick and decisive. It has been said that Primary Colours illustrates the fact that the American public deserves the politicians it elects because of the banal nature of the public itself. But I say that the politicians today are so uninspiring and so devoid of character that what matters to the public is indeed the length of their hair or the amount of weight they've put on. Elections today are about choosing the lesser of two evils, and the only interesting issue is which candidate is the greater evil.