Republicans in the administration and in Congress fought and fought for Nixon. It was all "party line" behavior that continues to this day.
It was only when Alex Butterfield (who just died) testified to the existence of the WH tapes that Republicans FINALLY caved. They couldn't lie and cover any more.
What still pisses me off is then Tennessee Senator Howard Baker famously asked: "What did he know and when did he know it?" as Republicans honestly trying to get to the bottom of the scandal. It was a great line! Republicans just wanted to discover the truth! For America!
But it wasn't!!! It was a tactic. The key word in his comment was the word "When." Baker was looking for a way to say that the Watergate break-in happened before Nixon knew about it. By 'those people!' Renegades!!! So, if Nixon didn't know about it until AFTER it happened, by rogue agents, then Nixon was innocent!! No impeachment. GOP does not burn to the ground.
Barry Goldwater, Senate Minority Leader Hugh Scott, and House Minority Leader John Rhodes, all defended Nixon constantly. And then they couldn't. THEY got caught covering Nixon's ass. They were out of options. Impeachment was a matter of days and they didn't have the votes in the House or Senate.