The Hill: Lawmakers struggle to pay for new transportation bill

From The Hill:

One of the biggest hurdles in passing a new $450 billion surface transportation bill this year will be finding a way to pay for it.  Revenue from the federal gas tax, the major funding source for the road and rail projects authorized by the transportation bill, is starting to flag as Americans drive less and turn to more fuel-efficient cars.  As a result, there may not be enough money in the Highway Trust Fund to pay for the new transportation bill.