Earlier quoted context omitted.
To be fair, support for removing Nixon from office among Republicans appeared rather rapidly, and there were still Republicans staunchly in support of him until the end https://fivethirtyeight.com/features/it-took-a-long-time-for...
Nixon had a whole lot of other things going against him.
Nixon was a generally popular president and it took a long time for his support to start slipping. His famous line "People have got to know whether or not their President is a crook. Well, I'm not a crook. I've earned everything I've got." wasn't nearly as in poor taste as it seems in hindsight.