"That's a real possibility," Amtrak spokesman Craig Schulz said Wednesday. "It's a real deadline, it's a federally mandated provision.
"The good news is that discussions are moving forward in a positive manner, and we're very optimistic we'll be able to come to an agreement in time for the deadline."
Amtrak has said it will end its $5.5 million-a-year contribution for running the Keystone service Oct. 1.
Pennsylvania, which already spends $8.8 million a year to underwrite Keystone operations, has its own financial woes, as state legislators did not approve a transportation-funding increase before recessing in July.
On Wednesday, Amtrak said ridership was up nearly 4 percent this fiscal year on the Keystone route, with 1.23 million riders in the 10 months ending July 31.
The Keystone service is the third-busiest of 28 routes supported by state governments, and ridership on the route has doubled since 2000. Tickets sell for as little as $27 each way, and express trains make the trip between Philadelphia and Harrisburg in 95 minutes.
Amtrak currently operates 14 daily trips in each direction. Passengers now pay for about 75 percent of the cost of Keystone operations.
In 2006, a $145 million upgrade to the 104-mile Philadelphia-Harrisburg corridor was completed, providing faster service and more frequent trains. The U.S. Department of Transportation gave Pennsylvania $40 million in 2011 to rebuild a rail intersection near Harrisburg to reduce travel time and improve reliability on the Keystone corridor.
The Pennsylvanian trains, with one round trip daily between Harrisburg and Pittsburgh, have seen a 3 percent ridership increase in the first 10 months of this fiscal year, to 181,400 passengers. Amtrak provided a $5.8 million operating subsidy for the route last year.
In March, Gov. Corbett announced an agreement with Amtrak to keep the Pennsylvanian running, but he said at the time that the state's $3.8 million contribution depended on legislative approval of a new transportation-funding bill.
So far, no such bill has been approved. Lawmakers say they may resume debate on state transportation funding next month, when the legislature returns to Harrisburg.
"We remain committed to preserving that service even as we deal with the legislature's failure to properly fund transportation," Steven Chizmar, spokesman for the Pennsylvania Department of Transportation, said Wednesday. "We continue to discuss the details of the agreement with Amtrak, and those discussions have been going smoothly."
Another possibility would be for Pennsylvania to contract with another rail operator, such as SEPTA or a private firm like Herzog Transit Services Inc. of St. Joseph, Mo., to run the Keystone trains.
In addition to Pennsylvania, the states still negotiating with Amtrak over subsidies are California, Oregon, Washington, Illinois, Indiana, Michigan, Missouri, Oklahoma, North Carolina, Connecticut, Maine, Massachusetts, New Hampshire, New York, and Vermont.
Contact Paul Nussbaum at 215-854-4587 or firstname.lastname@example.org.