The thing about Trump is that he will not win (he is just too damn unlikable, and unelectable; the same people who nominated Mitt Romney and John McCain will never support Trump), but until he doesn't win, he has *far* too much power and influence over the nominating contest. Faaar too much. Think about this: Because Trump is doing so well, the odds are that he will be within the top ten nationally when the first debate rolls around (and amazingly, probably close to the center of the stage, next to Bush, Rubio, and Walker), which also means he will push out one of the more serious but low-polling candidates (on Red King's NC poll, that would be Perry, Santorum, Graham and Jindal). Just think about that: Rick Perry was more then a bit of a buffoon in 2012, but he was still a governor of a major state (and a major republican state) for a long time, Santorum was the main contender to Romney in 2012, Graham is a major foreign policy expert and Senator (and is practically the long-lost brother of 2008's candidate, John McCain), and Jindal is a popular southern governor and one of the few minorities in the race; Governor Kasich of Ohio (remember Ohio? The state no republican can lose if they want to win the General Election?) wasn't even on that poll, but he would get booted too. All of those people would be booted off in favor of Donald Trump. And there's no criteria they've found yet that will exclude Trump but include important people like Jeb.
Basically, it's a brewing shitstorm of epic proportions. If Trump doesn't deflate soon, it's, well, it's going to be very amusing from a certain POV.