To me, ISU is clearly number 3 here and the gap to 4 is pretty significant. FWIW, I'd say Iowa, Nebbie and NDSU would be battling for number 4. I'm not counting the D3 schools but St Thomas and St Johns have pretty big followings too.I see so much Iowa State stuff taking over the Twin Cities, it's quite impressive actually.
I really think Hoiberg has something to do with this. He was so well-liked in Minnesota. Especially when people realized that he bought a cabin Up North just like their families had.
Also, the realization that, if your kid doesn't want to go to or can't get into MN or Wisconsin, there is a pretty affordable, top-of-the-line engineering school just to the south helped.