The polling numbers right now aren't going to reveal anything.
It would be interesting to gauge the public's mood by the number of internet searches on various terms:
Biden: segregationists, bussing (or is it busing? Bussing seems more like kissing, but busing looks like it should be pronounced like fusing, accusing, musing, ...)
Booker: Newark watershed scandal
Buttigieg: Racist police tapes
Harris: Larry Wallace harrassment
Sanders: Private jet, millionaire book deal
Warren: Faked bankruptcy research, that 1/1024 thing.