NEW YORK (CNNMoney) -- A bipartisan group of more than 60 senators -- evenly divided between the parties -- urged President Obama in a letter on Friday to take the lead in helping them come up with a comprehensive debt-reduction plan.
"We won't have any chance unless the president joins us in the effort," Sen. Mike Johanns told reporters.
Johanns, a Republican from Nebraska, and Sen. Michael Bennet, a Democrat from Colorado, shopped the letter around to colleagues in the past two days.
In response, the administration called the bipartisan effort a "positive development" and noted the measures it has taken to reduce deficits -- such as calling for a five-year freeze on non-security discretionary spending.
"[W]e will continue to work with members of Congress from both sides of the aisle to rein in our deficit, grow our economy and win the future," said White House spokesperson Amy Brundage in an e-mail.
The senators' letter doesn't endorse any particular debt-reduction plan, though it invokes the proposal put out in December by Obama's own debt commission.
"While we may not agree with every aspect of the commission's recommendations, we believe its work represents an important foundation to achieve meaningful progress on our debt," the letter says.
The commission's proposal would reduce deficits by $4 trillion over 10 years, overhaul the tax code by eliminating most tax breaks and reducing rates, establish caps on spending and revenue, and balance the budget by 2035.
The letter also does not lay out any ground rules for what should -- or should not -- be included in the debt-reduction debate. It only says, "we hope that the discussion will include discretionary spending cuts, entitlement changes and tax reform."
The point of the letter overall, Johanns said, is to signal that "we're ready to go and to get this done."
The idea came from two years of town hall meetings in Colorado, Bennet said. The refrain he heard from constituents -- both Democrats and Republicans -- was that they want a material way to address the debt.
Interestingly, he said, he saw much less division among Democrats and Republicans at his town hall meetings than he sees in the halls of the Congress.
The Bennet-Johanns letter - signed by 32 Democrats and 32 Republicans - is the latest in a line of efforts from some lawmakers and deficit hawks to build momentum for debt reduction.
"It is highly encouraging to see such a large, bipartisan group supporting serious efforts to tackle these fiscal challenges," said Maya MacGuineas, president of the Committee for a Responsible Federal Budget.
Among those signing on to the Bennet-Johanns letter was the so-called Gang of Six, a small group of senators that has been meeting regularly in the past few months to work out a way to turn the proposal from the president's debt commission into legislation.
The two co-chairmen of Obama's commission, meanwhile, have begun their own nonprofit project called Moment of Truth to inform lawmakers and the public about the country's fiscal problems and to help foster bipartisan compromise on a comprehensive debt-reduction plan.
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