Not wanting to continue driving in darkness and freezing weather, I stayed the night in Cedaredge. It is a small town, but it does have a Motel 6, a supermarket, and a couple of gas stations.
Like everything else on 65, the restaurants were closed, but the Motel 6 owner told me the supermarket was open to 9 pm, still 15 minutes to go. So I quickly went over there to buy a sandwich, and then went back to the motel to finish my registration.