I had considered writing a substantive reply, but then I resolved this down to two quotes:
We don’t need to welcome or embrace or fellate our own version of the Freedom Caucus. We need to kick them to the fucking curb.
We’re already to the left of him, and have been for a long time. Our progressive policies — if not our candidates — enjoy overwhelming support by a wide swath of the voting public.
And I realized that you weren’t making any sense. You want to run on progressive policies, AND kick the progressive voters “to the curb”, both.
Good luck with that.