This is what a record collector friend of mine had to say (to my mind he is a reputable source!):

"Madison doesn't seem to have had much of a music counterculture, which is somewhat surprising because Milwaukee had a very active underground music scene. there's a guy named dick campbell who put out a major label album called "sings where it's at" that's supposed to be dylanesque but i don't know if it's protest music per se - anyway, it sounds like he's from wisconsin, but the record was recorded in chicago so i don't know if he was operating out of chicago or not. he died a few years back.

"there's also a record by a madison wisconsin singer-songwriter named john villemonte called "people like you" but i don't know how activist it is in nature (and it's from 1976, which suggests that it's more introspective than political in nature, as much post-watergate folk material is). that said, he still seems to be around, so he might be a good resource for finding out more information about the late 60's / early 70's scene."