We know that David Duke supported Trump. We don't know of anyone associated with the KKK supporting Hillary. That the voters don't care is to their discredit.
We do know of Hillary's mentor, he claimed to have left the KKK. We know of other KKK Grand Master who have claimed to have donated to Hillary. It's all just claims and accusations to smear the opposite opponents in the election cycle. These are not important issues. Voters knows these are just election smears.
They claimed to have donated $20,000 to Hillary. The website claimed the claim is false.
We will never know, but more importantly, the voters didn't really care who the KKK was supporting, as the election results have shown.