Why the KKK supports Trump is rather telling about what Trump stands for, as is the fact that he has retweeted numerous white supremacists. It's not exactly that it's a one-way street where he can't help that they vote for him; he likes them, courts, them, retweets them, and has never distanced himself from them.
Trump? Or his campaign? Some people in his campaign have a tendency of denying everything he says. If it's Trump, it would be a first. He tends to waffle around it and give non-answers, because he doesn't want to drop his allies, but doesn't want to be seen supporting either.