With an obstruction of justice investigation into the president now more or less confirmed, will Republicans finally dump Trump?

Or are they craven enough to stick through this circus to the end?

Donald Trump has officially admitted that he's under investigation.

In a tweet sent out this morning - the president said:

"I am being investigated for firing the FBI Director by the man who told me to fire the FBI Director! Witch Hunt"

In case it wasn't clear, "The man" Trump is referring to in that tweet is Deputy Attorney General Rod Rosenstein, who appointed former FBI director Robert Mueller to be special counsel for the Russia investigation.

Rosenstein also wrote the memo justifying Trump's firing of James Comey.

If Mueller finishes his investigation and confirms obstruction of justice and Rosenstein recommends impeachment, will Republicans in Congress actually impeach Trump? Is Trump actually just priming the pump to ensure that his fate is a political one?