Honestly I don't think you'd see a partisan ruling on this. There is an originalist argument that Congress has no power to regulate immigration and that it is

Honestly I don't think you'd see a partisan ruling on this. There is an originalist argument that Congress has no power to regulate immigration and that it is the sole duty of the executive, but there are myriad ways the justices could get around that if they so desired. I'm no expert on the court, but I would imagine it would break 6-2 or better against the EO.