Maybe you haven't been paying attention, but the fact that republicans hate him makes him more popular. Trump being hated by the GOP is his main appeal. If he were one of them, I'm sure most of us would rather vote for Hillary.
This was Bernie's main appeal as well. I really wanted Bernie to win. Americans are sick of this inner party bullshit where it's 10 close friends taking turns leading the country. Our political system mirrors that of Russia, minus all of the killings. Putin was president then he was prime minister or something? After that he'll be some newly created position like prime president or governor general, and we'll all know that he's still the leader. In America we have HW Bush leading the CIA, then leading the country, then his son leads the country, and then his other son (Jeb) runs to lead the country. Bill Clinton was president, then his wife was secretary of state, and now his wife will be president. How long was Rumsfeld a member of the inner party? He was there since Reagan. Even Putin would admire that level of persistence.
We elected Obama because he was an outsider. His "hope and change" line changed immediately after he was in power and he was briefed on the way things really run. Now he just looks like a defeated man. He's obviously stressed out, and he's forced to give speeches for things he really doesn't want, such as proposing a war against Syria. He golfs all the time because he knows his job is ultimately meaningless and he has no power over the other oligarchs. We see hope in Trump because he seems like the kind of guy who rather die on his feet than play golf on his knees. We want to see Trump secretly murder the other oligarchs. If his balls are as big as he claims, he'll not-so-secretly kill the opposition. He could do what Erdogen just did in Turkey - stage a fake coup then begin the great purge.