Impeachment is the only (Constitutional) way to remove a sitting President.
When a President becomes a threat to the success of his own party, the leadership of that party will cooperate in removing him. Remember Nixon? It was the Republicans (led by Goldwater) who forced him out.
But, that was nearly 50 years ago...and a lot has changed in both parties...
Somehow I just don’t believe democrats would remove any democrat President...
That is pretty sad to say. I believe the corruption is so deep in DC, that men/women of integrity no longer exist there or if they do, are incapable of standing against the corruption.