I don't understand the intercity vs. intracity comment -- The NLX is supposed to be more of an intercity service, likely operated by or at least branded as Amtrak. Amtrak used to run a train on the line until 1985. Toward the end, it was a once-daily service in the summer but only ran on Friday, Saturday, and Sunday from October to April. It took 3-1/2 hours to make the trip -- not much competition for a car, though I suspect there have been plenty of bus services over the years which have had schedules like that.
It probably wouldn't cost all that much to simply restore the old service -- Back in 2006, it was claimed that
it would only cost $89 million. There is something to be said for slow, minimal services -- it wouldn't attract enough riders to be free from annual subsidies, but the overall cost would be a lot less. The current proposals for an 8x-daily train put the price tag around $750 million -- You can subsidize a slow, infrequent train indefinitely for that cost differential, but this is a route that has been shut down for much less. It was once put on the chopping block over a
paltry $27,000 deficit. A faster train would attract far more riders, though.
But it's also worth pointing out that this service is aiming for funding from a Federal Railroad Administration program that would pay 80% of the cost. The overall outlay for the state and local governments will probably be around $160 million, not much more than what it cost the state for Northstar (which only received about a 50% match).
Anyway, to address redisciple's point, the
Illinois Zephyr only has two daily round trips over the entire route (the second daily train is called the
Carl Sandburg). A little over 60% of the route is shared with the long-distance
California Zephyr and
Southwest Chief trains, which confuses things a bit. They could be cannibalizing riders, though Amtrak sometimes shifts things around, so that 225k number could be the actual ridership in the whole corridor.
The closest analog in the Amtrak system to a potential NLX train is probably the Boston-to-Portland
Downeaster. It has 5 daily roundtrips on a somewhat shorter corridor (116 miles vs. 150), though the travel time is about 25 minutes longer than driving would be (at least in free-flowing conditions). That carries 520k passengers per year, and has a 65% farebox ratio (assuming
this is the source redisciple used).
The Northern Lights Express would probably need to carry 750k passengers per year to break even, at least according to
this 2007 study. It might work with fewer passengers if the frequency was only 6x or 4x daily -- Maybe that would work for seasonal variation in ridership. It's hard to say whether they'd actually achieve that level, since I think the fares would be higher than what the
Downeaster charges (probably $35 one-way vs. $20 or so). People might be discouraged by that, but then again, the distance is longer and it'd be faster and more frequent.
At this particular moment, I only think there's a 50/50 chance it could fully live up to the projections. But even if it falls a bit short of projections, my sense is that the subsidy would end up being similar to what it'd cost to fund just a single slow train each day...