Sen. Joseph I. Lieberman (I-Conn.), chairman of the Homeland Security and Government Affairs Committee, is leading a bipartisan quartet seeking changes to the U.S. Postal Service. (Andrew Harrer/Bloomberg)

Sens. Joseph I. Lieberman (I-Conn.), Susan Collins (R-Maine), Thomas Carper (D-Del.) and Scott Brown (R-Mass.) are set to unveil a bill “to pull the USPS from the brink of financial failure,” their offices said Tuesday.

Aides don’t plan to publicly unveil details in advance, but some familiar with the negotiations said the new bill merges components from separate proposals previously introduced by Carper and Collins — the two senators who most closely track postal affairs.

Carper’s bill essentially gives USPS everything it wants — the right to end Saturday mail deliveries, close post offices, raise postage rates beyond the rate of inflation and return at least some money paid into federal retirement and health-care accounts to address billions of dollars in losses.

Collins’s bill would keep Saturday mail deliveries while restructuring USPS’s labor costs.

Notably absent from Wednesday’s announcement is Sen. John McCain (R-Ariz.), who is sponsoring the Senate version of a House bill written by Rep. Darrell Issa (R-Calif.) that would establish a financial control board to address postal finances and potentially lead to hundreds of thousands of postal worker layoffs.

Aides familiar with the plans said McCain plans to keep sponsoring his current bill.

Follow Ed O’Keefe on Twitter: @edatpost

Further reading:

Postal Service could lose $10 billion this year

Job cuts the focus of intense House Postal Service debate

John McCain joins the Postal Service debate

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