The Senate is scheduled to take up legislation Tuesday to keep federal highway money flowing to states, with just three days left before the government plans to start slowing down payments.
The House passed a $10.8 billion bill last week that would pay for highway and transit aid through the end of May 2015 if transportation spending is maintained at current levels.
But senators who say the House bill uses budgetary gimmicks or who want to force Congress to act on a long-term plan to pay for roads and bridges are expected to offer amendments. If any of the amendments pass, it would set up an 11th hour showdown between the House and Senate.
The Transportation Department says it will begin cutting back payments to states on Aug. 1.