Just as more and more Illinois commuters were getting on board with mass transit, a stalemate over how to pay for a $4 billion backlog of state bills threatens to force thousands off the bus.

Last month, the Illinois Department of Transportation sent out a courtesy letter to transit agencies statewide warning them that their next round of reimbursement checks may be delayed.

From Decatur to Rockford, transit officials now face the prospect of not being able to cover their costs if the state doesn’t make good on the outstanding payments. The Rockford Register Star reports that in a matter of weeks, some of the Rockford Mass Transit District (RMTD) services may even grind to a halt:

With state officials late to pay $3.8 million — and counting — in subsidies to RMTD, local officials are considering route cuts, fewer buses or a fare hike. There’s even fear the district could suspend service by the end of the year. [...]

The state subsidy is half the Rockford district’s operating budget, and service continues because of a line of credit and other revenue. But Brown said if the state doesn’t catch up soon, those other sources will be maxed out.

As in many parts of Illinois, mass transit ridership in the Rockford area is way up these days. Higher gasoline prices, fewer car loans, and a flat economy have led to a 22 percent increase over last fall, RMTD reports.

While the trend has encouraged mass transit advocates, cutting services now would present a major setback.

But that doesn’t have to happen, according to Jackie Grimshaw, transportation director of the nonprofit Center for Neighborhood Technology. “We can fill the gaps now with transit agencies if the governor would respond to a practical approach,” she said.

That “practical approach” she’s referring to came from Comptroller Dan Hynes last week. By taking out some short-term loans, Hynes says his office could begin digging out from under the mountain of unpaid bills. The state would then repay the debt as future revenues trickle in.

Gov. Rod Blagojevich shot back with his own proposal for getting the state’s finances back on track. He requested additional authority to cut agency budgets, borrow money, and request help from the federal government.

Grimshaw calls the latest power play another example of the state’s “failure of leadership.”