Sen. Ron Wyden (D-OR) and Rep. Paul Ryan (R-WI) are joining forces to reform Medicare in a way that both say will save the social safety net.

The plan (PDF), set to be officially unveiled at the Bipartisan Policy Center Thursday, would give seniors the option of choosing between new private insurance programs and a form of traditional Medicare.

Like the plan Ryan introduced earlier this year, this new proposal would still provide seniors with a set amount of money in the form of vouchers, but it's more generous than Ryan had proposed because "premium support" would fluctuate with the actual costs of health care.

The bipartisan-duo is proposing an annual growth rate based on nominal gross domestic product plus 1 percent instead of basing it on the cost of inflation as Ryan originally wanted, something that would not have kept up with skyrocketing health care costs.

Beginning is 2022, seniors would be forced to use their vouchers to buy coverage through a Medicare "exchange" -- which would also include private insurance plans. Unlike Ryan's plan, private companies would have to agree to offer plans at least as comprehensive as Medicare, and they would have to agree to cover any senior regardless of medical history.

Seniors would be responsible for paying out of pocket for any costs above any beyond the voucher.

In agreeing to the new plan, Ryan gets political cover from opponents who said that he wanted to "end Medicare," but he is also admitting that parts of President Barack Obama's Affordable Care Act are viable.

Both men told The Washington Post that the new plan would not necessarily even save the government money, but they hoped it would work to stem the rising costs of health care by allowing seniors to chose the plans with the lowest cost. But if that gamble fails, seniors could be left paying the difference.

"[T]his is bad policy and a complete political loser," one senior Democratic aide told Taking Points Memo's Brian Beutler. "On top of the terrible politics, they even admit that it dismantles Medicare but achieves no budgetary savings while doing so — the worst of all worlds. Thanks for nothing."

Of course, Wyden disagrees on that point.

"I will never do anything to shred that or weaken it or harm [Medicare] in any way," the senator from Oregon said in an interview with Politico. "I simply believe that there is now an opportunity for progressives and conservatives to come together and to strengthen the program for the long term and particularly, deal with the costs and demographic challenges."