BTW, Trump has negatives that are at Hillary levels. With that in mind...
... If I am not mistaken, Romney was at 51% negative in national polls but that was after he had secured the nomination and went through the GOP primaries - not before them."
Yup.
http://elections.huffingtonpost.com/pollster/2016-national-gop-primary
But the trajectory is good. All of Trump's numbers are going in the positive direction, including his "negatives". During the Republican nomination process, all smart Republican candidates appeal to Republican voters, and focus on their Republican competitors.
In order to skew a poll, CNN can add independents to give garbage data.
Trump is dominating a 16 person race, 40% of Republicans choose him as first or second.
When Trump secures the nomination, the same skill set he uses to become the nominee, he'll use to win the White House.
For Trump to win primaries and caucuses, he has to resonate on his message:
He's the smartest, most competent, most able.
His competitors are undesirable, and not smart, not able, not competent.
His ideas are the best.
Hillary is not immune to this strategy, she has just been spared the media glare, and the wrath of Trump. In swing states, she has been imploding however.
Prediction: Hillary will not be the Democratic nominee. And if she is, and faces Trump in a two party race, he clobbers her.