No. 6: Ohio

  • Proposed closings: 9
  • Unemployment rate: 8.1%

Ohio's Postal Service operations are set to undergo major restructuring. According to the Springfield News-Sun, a processing and distribution center in Dayton will be closed; operations in Akron, Canton and Youngstown will relocate to Cleveland; Toledo's will be divided between Columbus and Michigan; and Steubenville operations are set to move to Pittsburgh. Ohio is the seventh-largest state by population.

No. 5: Kentucky

  • Proposed closings: 9
  • Unemployment rate: 9.1%

The closing of nine processing centers in Kentucky may make next-day delivery a thing of the past for people in the state. According to David Walton, USPS spokesmen for Kentucky, as quoted in The State Journal, "Right now there's a time frame of one to three days for delivery (of first-class mail). We're going to be changing that to two to three days." Processing centers in Lexington, Bowling Green, Campton, Elizabethtown, Hazard, London, Paducah and Somerset will be shuttered at some point during 2012.

No. 4: Pennsylvania

  • Proposed closings: 12
  • Unemployment rate: 7.6%

The post office is closing 12 processing centers in Pennsylvania, including those in Lancaster, Altoona, Erie, Greensburg, New Castle, Reading, Scranton, Washington and Williamsport, as well as its southeastern operation. Pennsylvania, the sixth-largest state, has an unemployment rate that is significantly lower than the national average.

No. 3: New York

  • Proposed closings: 12
  • Unemployment rate: 8.0%

New York's postal system will see a lot of change this year. The Postal Service will be shuttering customer service mail-processing centers in Amsterdam, Binghamton, Glens Falls and Plattsburgh. A surface transfer center in Binghamton; processing and distribution centers in Brooklyn, Buffalo, Newburgh, Flushing and Garden City; an annex in Melville; a logistics and distribution center in Bethpage; and a delivery distribution center in Monsey will also be closed. New York is the country's third-largest state.

No. 2: Georgia

  • Proposed closings: 13
  • Unemployment rate: 9.7%

The USPS plans to close 13 processing centers in Georgia this year, including centers in Acworth, Albany, Athens, Augusta, Cartersville, Columbus, Douglasville, Marietta, Savannah, Swainsboro, Valdosta and Waycross. Some processing duties will be sent outside of the state. For example, some mail-processing operations of the Augusta Processing and Distribution Facility will soon be handled by the Columbia, S.C., center, according to The Augusta Chronicle.

No. 1: California

  • Proposed closings: 14
  • Unemployment rate: 11.1%

Fourteen postal centers will be closed in California -- more than in any other state in the nation. Centers to be closed include those in Bakersfield, Industry, Long Beach, Pasadena, Stockton, Petaluma and North Bay. According to USPS spokesman Augustine Ruiz, as reported by San Diego radio station KPBS, overnight mail will be delayed by at least a day if the delivery address is farther than 90 miles from one of the remaining processing centers. Ruiz also notes that employees will be given the option to follow their jobs to the centers where the work will be moved.

Click here to become a fan of MSN Money on Facebook

More from 24/7 Wall St.: