They need to take a page from conservative parties in Canada and Europe. Specifically, they need to embrace the scientific consensus on climate change, as well as support some form of universal health care. They also need to embrace policies favorable to demographic groups other than white men.
They are pretty favorable toward Jewish people for the most part
Jews are a tiny portion of the population, and this group isn't getting any bigger... also, even if the GOP tries to paint Democrats as "anti-Jewish", Democrats will still continue to win the Jewish vote by a wide margin, as they have for many years now.
The GOP needs to win over a substantial number of Hispanic and Asian voters, as well as getting back to at least W. Bush numbers with college educated whites, if they want to remain nationally competitive in the near future.
I personally believe the GOP will eventually adapt, since this is a two-party system and I can't see them just continuing to run on Trumpism when it won't work anymore. I expect them to be in the wilderness for some time before they realize what they have to do to win elections again, though.
