BUT WHAT DOES HOLLYWOOD WANT YOU TO THINK!
Take violence, for example. I think the template for violence was establish a long time ago with Hollywood. The movie Easy Rider (1968) shows the hippies are peaceful and the rednecks are violent. From that its easy to make the connections that hippies = peaceful = Democrats and rednecks = violent = Republicans. That is what Hollywood has given us ever since the 60s: the conceptual building blocks that form our views. We grew up with this in the air since kids.
In the movie Pleasantville (90s) people go back in time to remake the 50s into the morally lax, peaceful, colorful 60s. The mayor is a holdout and is violent Republican. And this brings up another point: if the Republicans arent rednecks they are a cabal of evil business men who use violence for profit (Sum of all Fears, Shooter, etc.). Again, to reiterate the template: hippie = peaceful, non materialistic, cool = Democrats; Rednecks and businessmen = violent, materialistic, uncool (look at Mr. Lebowsky from the Big Lebowsky) = Republicans. As well, Democrats are young and say yes, Republicans are old and say no. This is what Hollywood wants you to think and, more importantly, wants you to feel is true.
Sum of All Fears was the worst. The original book was a coherent story, with the bad guys being Palestinian terrorists. The movie clumsily replaced them with a rich dude.