I always laugh when I hear Republicans being dismissive of any single idea merely because more than one reason is offered.  The truth of the matter is that each of the causes probably contributed to the loss.  Are some of Trump's supporters white supremacists?  Absolutely.  

Did Russia, WikiLeaks, James Comey and Bernie Sanders also contribute to her defeat? Yes. Yes. Yes. And Yes.  

I don't think anyone can argue that all Trump's voters, voted for him, rather than against Hillary.  The same is true of her voters.  Do the reasons cited above contribute to the number of those who voted against her?  Again, absolutely.