Most of the cult might be beyond reach, but some might be peeled off.
I would suggest that the third of Americans who didn't vote in 2020 might be susceptible to a compelling message.
The American economy is an amazing thing, when it bounces back it really bounces back. It papers over cracks but keeps rolling along, fingers crossed there isn't another financial crash and you'd better hope that the Democrats reap the political capital.
Pelosi is milking it for all it's worth. Without wishing to appear callous, that crying Policeman is political gold for the Democrats, I've a gut feeling that time and tide and the steady drip, drip of grubby revelations exposing just how odious the GOP really is might well be their undoing, now that Trump no longer has the bully pulpit.
Good luck.
We've still got our bargain basement Trump with no prospect of getting him out any time soon, and our coiffured buffoon has no fear of the opposition coming out with a compelling message. Starmer wouldn't recognise a compelling message if it came crashing through the ceiling and killed him.
PS: I'm assuming you're an American and not an ex pat Brit. I'm acutely aware that as an American you have a dog in the race and I do not, plus you're on the ground and I am not, and the important point, it's your bloody country and not mine. You know it intimately, it's yours and you love it, so you have a right to feel these things on a visceral level, as I do about my country's clusterfuck.