If Rubio gets second here, he’ll win the nomination. The party will coalesce around him and Bush will be out before SC and FL. Then, Rubio and the GOPe machine will be in full force to win FL and ride that momentum. He’ll do quite well here if he has momentum even though he and Bush have been terrible in the polls to date.
I think the Canadian is going to win.
If your scenario holds Rubio will need a lot of Dem voters because a lot of Republicans will stay home in November.