Donald Trump could run as an independent as he has threatened to do. It would take a serious organizing effort to get on the ballot as an independent in most states; there is no evidence that Trump has started such an effort which would likely alienate him further from the GOP. Some states, Ohio is one, have laws which might bar him from running. But what if he did?
Don’t get your hopes up, Democrats–depending on who the candidates are, Trump might draw more votes from Democrats than from Republicans. If the Republicans choose a candidate with right-wing appeal, Republicans would have little incentive to turn their backs on that candidate. Whoever the Democratic candidate is, there are sure to be Democrats who would cast a protest vote for Trump.
Then there is the electoral college–local issues might influence Trump’s appeal. In TX or AZ, his views on immigration might be important. Also, consider ethnic groups in certain states; would Trump appeal to ethnic and minority voters disappointed with Republicans or Democrats? Would gender groups, men or women, be influenced?
Trump is unlikely to run as an independent, but if he did it would make the election very interesting.
New NY 23rd 
I predict that Mr Trump will self-destruct. He is a victim of his own narcissism. All candidates are somewhat narcissistic, I mean, you have to be to assume that you deserve to be the most powerful person on the globe. But in his case he can’t hide it. He is entertainingly hostile, but in the end , the GOP will turn to Bush or Walker in my opinion. Bush more likely.
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It’s actually preposterous that Donald Trump’s appeal has skyrocketed past his TV programs and his real estate empire. That he stands as a viable candidate for President of the United States is depressing. Would all party affiliations jump on his bombastic bandwagon just to vote their displeasure of their own party’s choices? Sad if true.
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We have to realize that the Republicans are really two parties under one name. Bush was suppose to be the heir apparent to the nomination, but would a majority of Republicans want to have another Bush in office? (I don’t think so.).
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I agree. This current GOP schism reminds me of the Democrats who were split by the anti-Vietnam War movement. It costs them a few elections. Whenever a political party demand ideological purity it is on the way to becoming a religion, not a political organization.
A blog I wrote on the topic over a year ago.
https://josephurban.wordpress.com/2014/02/16/the-most-holy-church-of-the-republican-party/
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G. Will urges the GOP to purge the Trumpettes in his column in today’s Gannet papers. I think his view is considerably muddled–he argues that Trump’s supporters aren’t tea party people. In any case the focus of the GOP leadership for years has been to accommodate the fringe element.
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