I'm not sure if there is even a way to determine exactly who each individual person voted for in each election, except for going by their word. It's all kind of an irrelevant argument, anyway. Either way, it's not provable. What we do know is that Trump got less votes than both Romney and McCain. His turnout was weak. "low energy", as he would describe it. He lost the popular vote by a lot. Certainly not a mandate by any means.