Why do liberal Democrats think all conservative Republicans are stupid?

Today I was reading Sarah Palin's book, "Going Rogue." Now I know that politicans often have ghostwriters help with their books, and in fact John McCain actually has Mark Salter given co-authorship credit, but I venture to think that the ghostwriters don't furnish the ideas: the politicians do that. And Gov. Palin's book is not the work of the idiot that the Democrats make her out to be! She may disagree with me on some issues, and I don't like that she's endorsed the candidate I disfavor for Governor of Maryland, but I expect that people will have differences on political matters. That's the nature of politics. But Gov. Palin does not, as I said, seem to be stupid.

But this seems par for the game. John Kerry, at one point in 2004, said "I can't believe I'm losing to this idiot!" This, referring to George W. Bush, the holder of a degree from Yale (with slightly, though insignificantly, higher grades than Kerry got at the same institution!) and another from Harvard. (How many presidents have had degrees from two of our most prestigious universities?)

The Democrats called Ronald Reagan an "amiable dunce," And other conservative Republican Presidents, such as Gerald Ford and Dwight D. Eisenhower, have had similar estimates made. Eisenhower, whose strategies probably contributed more to defeating Germany and Italy than any other man!

No, it seems that if a person is a conservative Republican, liberal Democrats won't admit that he might be equal in intelligence, or even superior, to a liberal Democrat. A strange phenomenon!