Why are you voting for a bully?

I am truly trying to understand why someone would vote for someone who is mean. He acts like a 12 year old on Twitter. Some of his tweets are downright cruel. Between calling Rosie O'Donnell a loser, saying Katy Perry must have been drunk when she married Russell Brand, calling the President a Psycho! or that there will not be another black president in a while because of his abilities, saying the Emmys are crazy for letting NPH host...the list goes on. I just do not understand why ANYONE would think this guy would be a good President with such childish behavior.