Nixon was going to be charged with obstruction and they had the votes to remove him from office.  Clinton was impeached for 2 things, one was obstruction, the other was perjury.  So, the precedent has already been made for impeachment for obstruction.  I am unsure if the House and Senate would vote to remove him, it seems that many of the Rs really dislike Trump and how he has handled things so far, so I could see them removing him in favor of Pence, who is a more mainstream Republican.

All of that being said, I would rather see an ineffective Trump in the White House than a probably much more effective Pence.