If the GOP somehow found a way to overturn the results and Trump got a 2nd term, McTurtle's majority would be F'd in the A in 2022.
As it stands now, he needs to win one home game in Georgia, then he can probably count on the out-party's usual enthusiasm advantage in the mid-term to potentially keep the Senate...likely for another 6 years at least.
What Mitch McConnell does is what Mitch McConnell views as best for Mitch McConnell. For profit prison donations to Mitch vs Trump's signature legislative achievement, federal sentencing reforms. The election security the Republicans are now so interested in. Foiled for over a decade because Mitch was on the payroll.
I'd rather have Chuck Schumer (vomits) running the Senate and Trump in the White House than have Biden in the White House and Mitch running the Senate.