It's interesting how persistent this meme of Republicans being "on-the-cusp-of-throwing-Trump- under-the-bus-to-save-themselves" is in progressive circles lately. We seem to gloss over the crux of the entire problem; that of Trump's deep and abiding popularity among Republicans. This is no small matter, and one which there is absolutely no way around, for Republicans as well as Democrats.
Take Mitch's situation: he is actually very unpopular in his own home state of Kentucky, with an approval rating of 30-34% there. Hence, he currently finds himself in a very tough battle for his own Senate seat next November. Trump, on the other hand, has an overall approval rating of about 65% in Kentucky. Since that state is evenly split among Democrats and Republicans, and assuming the vast majority of (if not virtually all) Democrats disapprove of Donald, that would make Trump's approval rating among Republicans in Kentucky (which, yes, I can find no specific data on) is probably even higher than the 80-90% he currently enjoys nationally among Republicans.
So, would Mitch McConnell take the lead in removing from office a sitting President (who also happens to be the head of the Republican party), and who is about 3x as popular among Republicans as McConnell is in his home state, in the midst of an election year? No, because Mitch actually needs Republicans to vote for him an awful lot more than he needs Democrats or even Independents to do so.
Now, multiply this by all of the Republicans who want to be re-elected next year, or at least need to be able to go home to their constituents without being tarred and feathered.
It's a bit like the owners of the New England Patriots deciding that Tom Brady is costing them just too much money, so they go ahead and trade him.
I'm sorry, but if Republicans haven't turned on him by now, I'm afraid they are never going to remove Donald Trump from office.