Just the numbers don’t match up enough to say “much of” those uneducated whites were union members. By your account 62% of 60 million (# who voted against Obama) were uneducated whites, about 38 million. There’s only 14 million total union members in the U.S. - that includes black and educated union member. Istm safe to assume the vast majority of noneducated whites who voted against Obama were NOT union members not “much” of them.