A century of research in psychology offers ample evidence that with enough time, repetition, and peer pressure, people can convince themselves that just about anything is normal, socially acceptable behavior. The dumpy guy in the next cubicle or your cookie-baking mom are perfectly capable of rounding up the Jews or surrendering their lives to the Great Leader if enough people around them are doing likewise and there are enough messages that it's OK. Hannah Arendt wrote extensively on the banality of evil – the idea that Nazi Germany, for example, was composed of normal, even boring people for whom the deviant had simply become normal. After a few weeks they don't even notice the smell of the crematoria.
That said, please recognize that the use of a Nazi example does not mean that I am about to imply that Republicans are Nazis. They've just created an atmosphere in which the aberrant has become so normal that no one even questions it. Surround yourself with enough crazy and apparently no one stops to wonder, "Hey, are we completely goddamn bonkers?" after a while. Or they ask someone even crazier and are reassured accordingly.
I don't believe that DailyKos/Research2000 is the finest of all polling organizations, but the operation is pulling large enough samples for all of us to be sufficiently alarmed by their recent poll of self-identified Republicans. In short, there are about 1/3 of Republicans who have some grounding in reality. They believe President Obama was born in the US. They don't believe he should be impeached given the complete absence of Constitutional cause for doing so. About 40% of them don't believe "President Obama wants the terrorists to win."
The other 2/3, well, they're quite the other thing. They hold some seriously wacky beliefs. Beliefs of the "The moon landing was faked" variety. As you examine the poll results the raw numbers are startling enough – 24% believe the President "wants the terrorists to win" – but take a look at the "not sure" category. Another 33% are not sure. They're entertaining the idea. It's plausible enough to avoid ruling it out.
Almost 80% believe or aren't sure that Obama is a socialist. Three out of five don't believe he was born in the US. 20% believe ACORN "stole" the 2008 election and a whopping 55% consider it plausible. 86% think or aren't sure that Palin is more qualified (although that's technically subjective, so let's let it slide). 64% think he is or may be a racist who hates white people irrespective of the fact that he is, you know, half white. A whole 58% – look at that, a modest majority! – believe their state should not secede from the union. 21% demand immediate secession while another quarter, well, they're a-thinkin' bout it. 8% think gays should be allowed to teach. A majority oppose (or aren't sure about) teaching sex education in schools. Any kind of sex education. I'll tell you what 77% do think should be taught, though…creationism! 31% (plus 13% unsure) believe contraceptives should be illegal. Well, that should help things!
This should alarm Republicans. It probably does alarm the 1/3 of them who, you know, understand the difference between reality and paranoid conspiracy theories peddled by sweaty idiots on cable. They feel outnumbered and rightly so. These are the kinds of beliefs that belong on the lunatic fringe of any respectable political movement, yet pure insanity is now the solid majority of the GOP. It is mainstream. Hear enough conspiracy theories about how some dime-store group called ACORN could "steal" an election won by 150 Electoral Votes and it becomes, well, normal.