Senate lawmakers have passed a bill that would overhaul the finances of the debt-stricken U.S. Postal Service and potentially delay the planned closings of as many as 3,700 post offices. The measure authorizes nearly $11 billion for the agency to offer buyouts and early retirement incentives to workers as well as repay its debts. Senators also set restrictions on the closing of post offices in rural areas and delayed a plan to end Saturday deliveries for two years. The House has yet to schedule a vote on a rival bill from Republican Representative Darrell Issa. The Postal Service is set to begin closing more post offices and processing centers on May 15. It was plunged into debt under a controversial 2006 law that forced the Postal Service to become the only agency required to fund 75 years of retiree health benefits over just a 10-year span.