Should Rutherford win nomination I would agree but he is trailing Dem favored tea party candidate Brady.
One poll showed Brady in favor. I have my doubts about him receiving the nom again.
As for the other candidates: I think Rutherford is probably most likely, though Rauner seems to have the financial well being to do battle. Dillard would have a stronger shot with more conservatives fighting amongst one another, but seeing as that is not the case, it's a hopeless campaign.
Update: Turns out, Rauner's money advantage is starting to have a distinct effect on the primary, leading Brady by 7, with Rutherford at 14 and Dillard at 10 (yikes!).