SDSU pretty much has control of fandom for the vast majority of the state. Lived in Yankton for 4 years and don't recall running into many USD fans. Plenty of SDSU blue though.That dude bashing ISU is most likely a Husker fan. Have spent a lot of time around Vermillion and Yankton. There is no such things as a USD fan. They are mainly Husker fans that cheer for USD as well.