I predict Thune will NOT push the SAVE Act through to passage. Thune does not take orders from other Republicans Senators (except one) or even South Dakota constituents as far as I can tell. He seems to me to take his marching orders from Mitch McConnell only.
Rumor has it that Thune is the Big Ag [Monsanto, Cargill, Bayer, ADM, etc,] Senator.
Conservatives of So. Dak.?
Not so much.
He could be Cornyaned in 2028.