Spirit has round-trip flights from Dallas (DFW) to Minneapolis (MSP) for $71-$76, NONSTOP. Flights August to October. Weekends available. Origin/Destination reversible.
Note: Spirit fares do not include a free carry-on bag. Only a small personal item, like a Jansport City Scout backpack is free. You can avoid paying for seat selection if you accept the randomly assigned seat prior to boarding.