This may surprise you, but I wouldn't hesitate to go straight through St. Paul then Mpls. on I94. As long as you don't go through there between 3:00pm-6:00pm you shouldn't run into any major traffic delays.
If you really want to circumvent mpls, you could spilt off and take 694W before you get to St. Paul. 694W will go N for a while, then head back W until it becomes I94 again.
Traffic in the twin cities is nothing compared to Chicago. If you can survive Chicago, you'll have no problems.