If they think he is going away, I don't think they have a clue. He killed Clinton in Minn taking like 62% of the vote in the primaries there. He already has a huge following when compared to any of the other folks looking for the nomination. It's going to be fun to watch because the field might be as big as the 2016 Republican field. All against President Trump!
Also a large portion of their party is working to elect the 1st woman for the office. I think they are going to be even more split among themselves than ever.