They are not going to impeach him.
If they can convince enough Democrats to convict in the Senate, there might be some point in going forward.
Happened in Illinois, a couple of years ago, when the State Legislature decided to dump Governor Rod Blagoevich.
And that was a Democrat -controlled State Legislature, firing a Democratic Governor.
It all depends upon the charges, the motives, the prizes, and the behind-the-scenes negotiations.
If conviction were to follow, the POTUS becomes the ex-POTUS, the moment the Senate conviction is declared, right?
All allegiance owed by the Armed Forces terminates at that split second and transfers to the next in line of succession - something that much of the upper management at the Pentagon would probably be quite happy to see come to pass.
Given that the VP is already in the Senate chamber at that split second, it would be a simple matter of have the Chief Justice stop-by, at that moment, to swear-in the new one.
But it all depends upon whether a number of Democratic Senators can be turned.
After all, they would still have a Democratic President, to finish out the term.
But, as to whether a sufficient number of Democratic Senators could be 'turned' to convict, on High Crimes and Misdemeanors, once the charges have been conjured up, well..
That's very much a 'unknown' at this point - even though the Democrats are already running away from the President at the speed of light.
Democratic Senators from states with really large black populations probably would not dare help to convict the President in the Senate, in most cases, but Democratic Senators from states that are no so populated, might very well be able to get away with it, and defend the action amongst their constituencies.
It's a long shot - no getting around that - but stranger things have happened.
Obama should really consider backing down on this
Shamnesty-via-Executive-Order business.
It would actually end-up becoming his un-doing, and result in early job-dismissal.