Jack, allow me to suggest that this is a tad overwrought.
DU is a subgroup of the left wing of the Democratic Party. They are much smaller than FR and are our mirror image on the Left, only much more fanatical. Basically, what you have in DU are the shahid of the Democratic Party. In Palestine, these guys would be wearing vests made up of Semtex and blowing up buses. Since this is America, these guys just wail at the moon.
But it's the same thing. Extremists hate; that's just the nature of the beast. But most Democrats are not like the Totenkopfverbande who post there. Most registered Dems are like most registered Pubbies, and are not a bunch of loony, birkenstock-wearing lefties!
There is a whole lot less to the Red/Blue divide than we are led to believe.
Be Seeing You,
Chris