Yeah, crows and ravens have been symbols of disaster for centuries. I don't even know where the racism thing comes into that.
Jim Crow laws.
It might be a bit oversensitive to accuse Santorum of being racist for using crows in an anti-Obama video, but like I said, it's probably more likely that he and/or the producers of said ad didn't even think about the racial context.
No gbaji, it's not trying to find racism in anything. If they had used a snake instead of crows it wouldn't be racist. Unless it was a black snake of course.
They could have used pretty much any other animal besides a crow (or a monkey/ape) and it wouldn't have been offensive.