Looking back, the Texas Zephyr ran Denver to Trinidad in as little as 4:33, added to the Amtrak Trinidad to Albuquerque fastest time of 5:39 = total of 10 hours and 12 minutes...
What trip time would one be realistically looking at for a DEN-ABQ trip?
New Mexico actually had entered a contract to purchase the entire line up to the Colorado state line with this in mind. Also, BNSF had made it a condition of buying what New Mexico actually wanted, Belen-Lamy. The deal was phased, with transfer of ownership Belen-Lamy first. However, after an administration changed in New Mexico, New Mexico reneged on the deal. They ultimately settled with BNSF and the rest of the deal died.
Denver to Albuquerque is a potential passenger train corridor. I would think there is demand for a few round-trip trains a day between these cities. The two cities are 450 miles apart. A few corridor trains between these cities would increase passenger revenues to cover the fixed costs of the passenger train speed infrasteucure.
While Albuquerque is a corridor candidate, in order to get to Denver, a train would have to use the very heavily trafficked Joint Line north of Pueblo, CO. BNSF is pretty resistant to adding a passenger train to the mix without some major capacity improvement funded by NM/CO . BNSF would almost require New Mexico and Colorado purchase the Raton line as far as Trinidad.
I seriously doubt if that Denver to Trinidad time could be duplicated today, however...
That terribly uncompetitive, even at the old running times (compared to 6.5 hours driving). Under current conditions, my guess is running time would be 12ish hours. That would be a rough corridor train.