"a lot of it was (reportedly) emanating from / encouraged by moveon.org."

Reportedly? got any cites or proof? if not, it's speculation. And a random geek defacing a website doesn't mean it was encouraged.

"who would have guessed that democratic activists would turn out to be anti-semites?"

There are racists in every group, including Republicans. What's your point?

"anyhow, he's a republican now."

No, he's an Independent.