The influential seniors' lobby AARP has joined forces with the American Medical Association (AMA) to push senators to pass a bill next week to hike Medicare's pay rates for physicians.

Getting the Medicare payments, which will be slashed by 21 percent next year unless Congress acts, is the AMA's number-one priority. For the AARP, they are concerned that Medicare beneficiaries will have a hard time finding a doctor if the program pays physicians too little.

"The continuing threat of steep Medicare payment cuts jeopardizes seniors' access to care and physicians' confidence in the government's commitment to funding a strong and reliable Medicare program,” says a joint letter sent by the leaders of the AMA and the AARP to senators Friday.

Senate Majority Leader Harry Reid (D-Nev.) plans to raise a $246.9 billion bill on Monday that would scrap the current, broken system that sets physician payments under Medicare and boost the rates. The bill, however, is not paid for and faces opposition from Republicans and centrist Democrats.

Though Reid and Sen. Debbie Stabenow (D-Mich.) surprised practically everyone early this week when they dropped the bill and opened the proceedings to a floor debate next week, the AMA has sprung into action. On Thursday, the physician lobbying group rolled out a national advertising campaign to promote the bill. Democrats are eager to win the support of doctors for their broader healthcare reform legislation, which could come to the Senate floor before the end of the month. Fixing the longstanding problem with Medicare pay rates would go a long way toward winning that support.