Well, the Republican Party isn't fighting it because it's become an almost complete take over. IMHO, it began to take it's new form with the Tea Party movement (just after GWB). They were Hard Core Believers in their cause. The fact that that movement swept in so many R's into office made the appeal to Republican congress critters too strong to ignore. Then, with the help of talk radio, FOX and assistance from our enemies (Rus) and a savvy social media blitz, a sonic wall of lies began to pervade the republican conscience and it stuck. When Trump rode in of this wave of lies, which he almost expertly added to, grabbed the nomination. Some backroom deals about towing the line on certain republican objectives earned him more support of the power brokers in Congress. His win, I'm sure, solidified this new movement of 'Trumpism'. As talked about often, an alternate reality has now set in, any half sane republican has or will end their political service. The new movement has taken over - and has happened with Covid, it is more virulent than the last.
There is no recognizable 'Republican' party left. How this insanity ends is beyond me.