Is there anything that Trump could say or do (or has said and done) that would automatically disqualify him as a presidential nomination in your mind?
Sure there is. I don't know if there is any single sentence, but I support him because of the following:
- Unlike McCain and Romney, he can win elections. He has demonstrated that by winning 3/4 of the primaries/caucuses thus far, and he almost won the 4th one. He has an incredible nationwide lead in the polls compared to his GOP rivals.
And don't bring up his favourability ratings, they don't matter much at this point. If they were something to look at right now, then Carson and Sanders would be the front-runners on each side. Trump will focus on his cross-party appeal once he gets the Republican nomination.
- Trump has had an impact on American politics even before getting elected. He made the discussion about radical Islamic terrorism, illegal immigration, and political correctness a prominent one. Yes, there was talk about it earlier too, but not at the current scale. He has mobilized tens of thousands of people who didn't speak up earlier.
We waited for the Ron Paul revolution for 30 years. It never happened. He couldn't beat the GOP establishment, not to mention the progressive media. Trump mobilized people for his cause in months. His cause is not the same as Ron Paul's, but there are similarities.
- Apart from that, Trump is an intelligent guy who is not bound by the will of donors and special interests. He won't be able to deliver everything he promises and we all know that, but I think he has a much better understanding on how to get things done internationally than all those career politicians. Who knows, he might broker a deal with China and get rid of North Korean nuclear missiles. His strategy on how to deal with ISIS sounds much more reasonable than anything Cruz or Rubio or the Dems have said.
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So, if Trump started *consistently* doing and saying things that go against the above, I would reconsider voting him. If he started saying "Black Lives Matter", repeating the wage gap myth, claiming America needs more positive discrimination, then I would seriously consider other candidates. If he doesn't have a clear lead in delegates after Super Tuesday, I might question his ability to win elections.
Also, if Rubio started taking bolder stances on controversial but right issues, I would gain more respect for him. For instance, if he had brought up the fact that GWB was a disaster for the Republican party ahead of Trump, then his stock would have risen in my eyes. Same with Eminent Domain. That said, I have a hard time seeing him as anything but a weak puppet of his donors and special interests + the GOP establishment.