Alright prediction time!
To start with lets get some of my initial assumptions out of the way so you know where I am coming from with this and why I feel confident in calling it 90% over for Donald Trump.
1: He is not considered a Republican. He is an outsider running on their platform and once this is over they will try to distance him as far as possible from their "Republican" brand which is why he is so convenient right now since he can take all the baggage and debt with him on the way out.
2: Working in a close relationship with Donald Trump is hard, if not impossible. Relations always turns sour and falls apart it seams like. Trump has always functioned "best" when he is in command alone which won't work in American politics where he needs the support of his party.
3: Donald Trump is in a weak position in regards to for example having investigations against him and his businesses as well as a mountain of other stuff which seams to be ready to blow up in his face at any moment.
4: Donald Trumps political support base includes a lot of people who does not like him. They are useful pawns as long as Trump can control them but at the same time he will be in major trouble if he shows any weakness
Alright so what has happened now which might spell the doom for Donny? After a long string of very politically expensive moves both Donald Trump and the Republicans have more or less been cornered and someone will have to absorb the next blow and in this delicate situation Donald Trump decided to surprise fire the FBI director who at the time might be investigating Trump. There are still many questions surrounding this and it might turn out even worse but whats important is that this seams to have pushed some Republicans over the edge where they can no longer support Trump.
At this point one of two things will happen. Either Donald re-establish dominance and have Republicans step up and take some serious damage in defending Donald Trump himself.. Or the Republicans gets ready to take down Donald Trump themselves. What we see at this early stage however is that the Republicans are not unanimously automatically defending Trumps latest choice of firing the FBI director and has started to openly question him. This is very bad for Trump.
Republicans dont simply say this out of the blue, instead this is evidence that there is already a faction against Trump and that they are putting in the groundwork to potentially deal with him. I predict that even though its a very early stage we will see this as the turning point where Republicans openly start acting against Trump which might result in either a resignation, Impeachment or a completed FBI investigation against him.
We have still not seen any major movements in regards to the enemies he made while running for president inside the Republicans but its only a matter of time until the sharks circle the waters after smelling blood.
Pull up a chair and lets watch the game of thrones together. Its the season finale coming up!