The Republican party became a sellout, he should create his own Populist party to replace them.
Theodore Roosevelt use to be a Republican, but he created his own party called the Bull Moose party while in office and a majority of his supporters joined it.
Or, hear me out on this, we all start attending our local party meetings in order to effect party-wide change...
It's not a very difficult thing to do. People on here just need to stop being lazy slacktivists.
Edit: OP, how many doors did you knock or phone calls did you make during the election?