According to David Brooks on last Friday's PBS Newshour:
There is much more straight ticket voting now in the country than there was 20 years ago. And the paradox is as people get better educated, you would think they would vote more independently. In fact, they vote straight ticket, much more often as we get more college grads.
I think it's funny that an intelligent guy like Brooks considers this a "paradox". I guess he thought straight ticket voting on the Democratic side came from ignorant poor urban dwellers doing what the party bosses told them to.
But this development makes perfect sense to me...
I've always suspected "swing voters" were mostly pretty dumb. I mean, Nader's and Dean's claims to the contrary notwithstanding, there is a pretty big difference in ideology and in legislative voting between the two major parties. So to look at them and say "hmmm...I'm really not sure; I guess I'll vote for whoever I like the look of (or whose campaign commercial or simplistic slogan strikes my fancy)"--that's not very sophisticated.
When you get some edjicayshun, you are able to perceive those deep policy differences, and to formulate your own positions. Then it's easy to figure out which party is on your side.