If Trump can keep these kind of #s up for another 2 years, he’s got the keys to the nomination again
He already has the keys. I'm not the type to ever say "it is over" and certainly not 3 years before the primaries, but there needs to be one hell of a game changer if Trump is not to win it if he runs.
Trump is not a normal politician. The GQP is locked in a cult of personality, where your level of diehard support for Trump is all that matters. Short of prison, I don't see any scandal that could sink Donald Trump.
What makes it impossible for anybody else is that you can't run against Trump. When your main selling point is that you are a Trumpist, how could you run against the God Emporor himself? You would be a traitor in the eyes of the death eaters.
So basically I see only three likely scenarios right now:
a) Trump runs and easily wins. Barely anybody will even dare to challenge him. It will be like Hillary 2016 without Bernie Sanders.
b) Trump decides against running for whatever reason. Maybe he decides that he is tired of losing.
c) Trump is in jail or dead, so he can't run.
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So if I have to envision a scenario where Trump runs yet doesn't win, I think a number of things would have to happen. The most important would probably the GQP running a lot of Trumpists in 2022 who lose BADLY and an overall terrible result for the GQP. Also, something would have to happen that makes Trump fade from the headlines and media attention, which seems unlikely. Really important is also the emergence of a new leader figure that inspires some of the same religious devotion that Donald Trump does. Ron DeSantis seems like the most likely here, but then again, not really.
Anyway, I think this last fantasy scenario is not even in the same league of likelihood as the three top options.