I was considering the large number of students that live in minnesota, for whom d2 football was a complete afterthought. If you are unaffiliated with both schools, and pay attention to football, and live in minnesota, one school is going to be much more on your radar than the other. Is it really that ludicrous to suggest that the attention brought to NDSU's team in the mid-aughts would have dis proportionally improved the draw of NDSU for people inclined to be football fans, who would have otherwise been relatively more likely to go to UND?
In a pretty direct way, it does just come back to winning, only the lag-time might be longer for this sort of affect.