Trump is scum.
He does not give a rat's ass about the Constitution or about rule-of-law and actively takes pride in his ignorance on everything from Constitutional law to military strategy. (The fact that he runs his mouth off about the wars and yet couldn't even name the major terrorist groups or identify who funds whom was very telling.) He just wants to be King, not President, and will bully and tyrannize American citizens if given power to do so.
I will never vote for someone who actively seeks to compromise the First Amendment (so he can sue dissenting journalists into silence and laugh as protesters get assaulted), and who openly proclaims his intention to violate the Eighth Amendment (and insult other candidates for not doing such). His historical behavior on Second and Fourth Amendment matters is also quite disturbing, no matter how much he postures now.
And nor do I ever intend to vote for someone who wouldn't even disavow support for things like the Japanese-American Internment nor the Ku Klux Klan (Really? He doesn't know who they are? If he's telling the truth, then does someone that badly-informed have any place in the White House?).
I don't want to see a Democrat elected, but I would sooner choose Sanders than Trump. With Rand Paul long gone, I'm really hoping Cruz gets the job done. I get that people are frustrated with "the establishment", but lawless scum is lawless scum no matter its origin, and I'm not going to act to actively hand state-power (i.e., the claim of authority of legitimized-violence upon citizens, such as me) to such.