Hmmm, I dunno about that....I'd have to check to be ultimately sure but right now would bet they were spawned as 527's.
Those groups didn't even exist until after MFG did they?
Yup, I think both came along after Insane Feingold, but that may be coincidental. People from the Clinton administration were in need of a place to carry on their crusades. David Brock needed a leftie place to hang his hat after he defected from conservatism.
It may be that Soros decided to ramp up right after CFR, but these groups are not 527s, as their regular output is not direct advocacy for particular candidates. They are c3s.