Republicans win because they frame themselves as pieces of shyt and act accordingly.
Democrats try to be the "good guys" but then don't deliver, so they get hate no matter what. Try to be moderate? Fukk these do-nothing corporatists.
Try to be progressive? Fukk these candy azz libs....and Republican turnout goes up 50% for the next midterm election. Democrats don't vote during midterms. What that means??? Well it means that when the Dems do something positive, they don't get numbers at the polls and Republicans promptly force them to walk it back by winning.
Manchin is in a weird spot. He's the only Democrat capable of winning a Senate seat from West Virginia. He knows this shyt. If Dems tried to push him out, 10 Republicans would take his place.