A study looking at the possibility of reinstating a Denver to Seattle Amtrak route shows that it would cost $478 million to set up, carry 111,000 passengers a year, and produce $13.1 million revenue, at $46.2 million of direct operating costs a year (a net operating loss of $33.1 million).
The annual net operating loss per passenger per trip would be $298.19, despite the $118 per passenger per trip ticket charge. The operating cost is $416.19 per passenger trip. This is ignoring any allowance for the infrastructure costs -- even before depreciating any of the investment, a 3% interest rate on the money investment would be $14.3 million, $129.19 per passenger per trip, for a total cost of $545.38 per passenger per trip with service that would be much slower and less likely to be on time than commercial airplane service. It would be faster and not a lot more expensive, to simply subsidize commercial airplane tickets on these trips. An investment in bus service would likewise make much better sense. You can run a very nice bus service for $545.38 per passenger per trip from Denver to Seattle, and a high end bus service would be faster and more likely to be on time.
Passenger trains can be a great choice in some circumstances. But, long haul trips across a largely uninhabited part of the country, at conventional passenger rail speeds, is not one of those circumstances.