Closer to 10 hours to Denver or 11 to Dallas. Not that I'd want to go to either. Skiing adds 2 more hours to the trip. All the Great Lakes, all the murderous big MW cities, ( Chicago, StL, Memphis, Detroit, Mpls, even Pittsburgh and Cleveland ) are all closer to the Athens of the Midwest, than Denver is to DM.
I guess it depends on how fast you drive. But your post is spot on