Huh. I canvassed there during the 2008 election. I didn't even get funny looks, which has happened to me more than once when I went into the "wrong" neighborhood in Chicago.
In fact, I once pulled over into a gas station only to have the attendant tell me I needed to get into my car and drive off.
I've never once had an experience like that in SF.
In Chicago, not SF. Nothing like that has ever happened to me in SF, even as a white guy going door to door in Bayview.
Also, I wouldn't call it a "decent neighborhood," I just don't want to make it seem like you'll get shot for setting foot there, is all. I wouldn't live there.
In fact, I once pulled over into a gas station only to have the attendant tell me I needed to get into my car and drive off.
I've never once had an experience like that in SF.