(CNN) -- Rain, sleet and snow don't stop the postal service, but Thursday a group of senators said money problems could sink the institution by next summer.
The bipartisan group introduced a bill to save the service.
It would return a nearly $7 billion overpayment to the Federal Employment Retirement System.
Some of that cash would be used to buy out 100,000 workers.
The rest could help pay off debt.
The senators say if the postal service cuts services, it starts a death spiral.
"What we want to do is make sure slashing or eliminating Saturday delivery is truly the last resort, not a first option," said Sen. Susan Collins, R-Maine.
House Republicans favor the idea of ending Saturday service, and they call refunding the multi-billion dollar overpayment a bailout.