This story has been updated to include additional reporting.

WASHINGTON -- The big numbers from Paul Ryan’s budget: It will reduce spending by $6.2 trillion over the next decade and reduce the deficit by $4.4 trillion.

It also cuts the top income tax rate by nearly a third, from 35 percent to 25 percent.

A big part of the House Budget Chairman's plan rests on the assumption that President Barack Obama’s health care law will be repealed. Over the next decade, that would cut $1.4 trillion in spending alone, according to Ryan's budget. Those savings, however, wouldn't go directly to deficit reduction, because Ryan would also repeal the elements of health care reform that are aimed at raising revenue or reducing costs.

The Wisconsin Republican's budget spends less on nearly every major category of the budget. Over the next decade, Ryan (R-Wis.) wants to cut $389 billion from Medicare, the public health insurance program for seniors. Over the same period, Ryan's budget puts $735 billion less toward Medicaid, which benefits Americans too poor to afford private insurance. Discretionary spending on domestic programs is also reduced by $923 billion.

Two exceptions are security and defense spending and spending on Social Security, the public pension program for the elderly. Both are kept steady and relatively unchanged from Obama’s proposed budget.

A draft proposal from Ryan’s House Budget Committee says that under his plan, the national debt would be $1.1 trillion less than it would be over the next five years under Obama’s budget, and would add $3 trillion less to the debt than Obama’s budget proposal over the next decade. Ryan’s budget proposal would bring the debt held by the public to $13.9 trillion by 2016 and $16 trillion by 2021, compared to $15 trillion in 2016 and $19 trillion in 2021 under the president’s proposal. (The full national debt of just over $14 trillion also includes money owed to the Social Security and Medicare trust funds, but the public figure is the one normally used for budget forecasts.)

Though Ryan's plan would reduce the size of the national debt as a portion of the economy - which is the key factor when considering the country's obligations to creditors - the addition of new debt in the short term shows the gap between talk of not raising the debt ceiling by many Republicans and fiscal reality.

Ryan’s plan has $40 trillion in spending over the next 10 years compared to $34.9 trillion in revenues. Obama would spend $46 trillion in the coming decade while bringing in $38.8 trillion in revenues. So Ryan's plan would still result in the government spending $5.1 trillion more over the next decade than it brings in, but that’s less than the $7.2 trillion in deficit spending that Obama has proposed.

The most fundamental difference between the competing budget proposals is seen in the way they envision the size of government’s imprint in the economy, as measured by spending and revenues as a percentage of gross domestic product.

Obama’s budget plan would take spending as a percentage of gross domestic product (GDP), the total economic output of the American economy, from 25.3 percent this year to the 22 percent range for much of the next decade. But by the end of the 10 year horizon, his plan has spending back at 23 percent. Revenues, meanwhile, which are currently at an anemic 14.4 percent, would creep up to 19 percent by 2015 and then hit 20 percent in 2021.

It would be the highest amount of government spending since World War II. During the 12-year presidency of Franklin Delano Roosevelt, spending went from 8 percent of GDP to 41 percent, driven by FDR’s New Deal but even more so by war spending.

During Harry Truman's administration, spending was cut in half, from 41 percent of GDP down to 20 percent, and went down further to 18 percent under Dwight Eisenhower. It stayed at 18 percent of GDP through the John F. Kennedy presidency, crept up to 19 percent under Lyndon Johnson, and then went up to 20 percent while Richard Nixon was in the White House. Gerald Ford brought spending back down to 19 percent of GDP, it then went up to 22 percent during Jimmy Carter's term, down to 21 percent under Ronald Reagan's two terms and George H.W. Bush's four years as commander in chief. Bill Clinton brought spending back down to 18 percent of the U.S. economy.

No president since FDR has increased spending as a percentage of GDP by more than George W. Bush, taking it from 18.4 percent of GDP to 22.8 percent.

Obama’s budget does not show what happens beyond the 10-year window. So, compared to George W. Bush’s spending, he seems to be about on par. However, projections from the Congressional Budget Office (CBO) show spending growing at its current pace will grow to more than 26 percent of GDP in 2022, over 32 percent of GDP in 2030, 38 percent of GDP in 2040, and 45 percent of GDP by 2050, with the bulk of that spending driven by ever-rising health care costs.

Revenues under CBO projections would not move above 19 percent of GDP, leading to a gap between spending and revenues that would be difficult to sustain.

Ryan said a computer simulation program of what would happen in the future “crashes in 2037, because it can’t conceive of any way in which the U.S. economy can continue because of this massive burden of debt.”

Ryan’s plan would move spending back to historic levels, keeping it at 20 percent of GDP through 2030, and actually reducing it to under 19 percent by 2040. Ryan’s plan predicts revenues growing to 19 percent of GDP by 2040, allowing the national debt to be reduced over time.

The proposal landed in the middle of a busy news cycle where Washington is consumed with a spending fight over the current fiscal year budget, a much smaller portion of government spending that nonetheless will shut down the federal government if it is not resolved by Friday.

"Right now we’ve got some business in front of us that needs to be done," Obama told reporters Tuesday afternoon, declining to respond to Ryan's budget.

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[UPDATE: 4:36 p.m.] -- The White House later issued a response in the form of an e-mailed statement from White House press secretary Jay Carney that said the administration "strongly disagree[d]" with Ryan's approach, though they gave him credit for laying out a proposal to deal with the nation's deficit and debt. Here is the full statement from Carney:

The President believes that dramatically reducing America’s long-term deficit is essential to growing our economy and winning the future. Today, Congressman Ryan laid out his vision for how to do that, and he is right that we cannot solve our fiscal challenge by focusing on the narrow slice of domestic spending that has occupied so much of our recent attention. But while we agree with his ultimate goal, we strongly disagree with his approach. Any plan to reduce our deficit must reflect the American values of fairness and shared sacrifice. Congressman Ryan’s plan fails this test. It cuts taxes for millionaires and special interests while placing a greater burden on seniors who depend on Medicare or live in nursing homes, families struggling with a child who has serious disabilities, workers who have lost their health care coverage, and students and their families who rely on Pell grants. The President believes there is a more balanced way to put America on a path to prosperity. But despite our differences, all of us – Democrats and Republicans – have an obligation to find common ground in a way that is true to our values and meets our responsibilities to the American people.



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The reaction to Ryan's plan was predictably split along ideological lines, though even those who supported the broad contours of Ryan's plan did not embrace it in all its detail.

[UPDATE: 4:45 p.m. -- Rep. Jim Jordan, an Ohio Republican who leads a group of the House GOP's 175 most conservative members as head of the Republican Study Committee, told the Huffington Post he was happy with Ryan's plan, with one caveat.

"We like the concepts," Jordan said in an interview. "We think it’s a lot of good work: saving Medicare, putting in a cap that makes sense on Medicaid. We just think that a lot of the reforms in our budget we’re probably going to have to speed up because we’ve got to get to balance."

In essence that means that Jordan's budget proposal, which the RSC is expected to release in the coming days, would cut spending deeper and in a shorter period of time than even Ryan's plan.

Jordan said in a statement posted online Tuesday afternoon that the timeline for balancing the budget under his plan would be a decade.

"The RSC is working on a proposal that builds off the Budget Committee’s effort and gets the budget into balance within 10 years," Jordan's statement said.]

Robert Borosage, co-director of the liberal Campaign for America’s Future, delivered the harshest rebuke of the day to Ryan's plan.

"This is being hailed as courageous. It isn’t courageous; it is corrupt," Borosage said in a statement.

“Rep. Paul Ryan’s budget plan will push rising health care costs onto those least able to afford them – the elderly, the disabled and the poor," Borosage said. "It will do nothing to curb the rising costs imposed by the powerful complexes – insurance and drug companies, private hospitals – that now force Americans to pay twice per capita of any other industrial nation for worst results."

Rep. Chris Van Hollen, the Maryland Democrat who is Ryan's foil as the Budget Committee's ranking member, said the plan was a "lopsided approach" to deficit reduction that took too much from the disadvantaged and elderly in order to benefit wealthy Americans and big business.

"Behind the sunny rhetoric of reform, the Republican Budget represents the rigid ideological agenda that extends tax cuts to the rich and powerful at the expense of the rest of America – except this time on steroids," Van Hollen said in a statement.

Senate Budget Committee Chairman Kent Conrad, North Dakota Democrat, called Ryan's plan "partisan and ideological."

"He provides dramatic tax cuts for the wealthiest, financed by draconian reductions in Medicare and Medicaid. His proposals are unreasonable and unsustainable," Conrad said. "His plan is most troubling because it lacks balance."

However, David Walker, the former U.S. comptroller general and founder of the Comeback America Initiative who is generally a fiscal hawk, said Ryan "should be commended for having the courage to lead in connection with our nation's huge deficit and debt challenges."

"His budget proposal recognizes that restoring fiscal sustainability will require tough transformational changes in many areas, including spending programs and tax policies," Walker said.

Among the 2012 Republican presidential hopefuls, former Minnesota Gov. Tim Pawlenty was quick to comment on Ryan's plan.

“Thanks to Paul Ryan in Congress, the American people finally have someone offering real leadership in Washington," Pawlenty said, but he otherwise steered clear of the details and focused on the coming fight over the debt ceiling.

"President Obama has failed to lead and make tough choices his entire time in the White House. While the budget is going to be debated for several months to come, the more immediate issue we face is President Obama’s plans to raise the debt ceiling next month. That's a really bad idea," Pawlenty said in a statement.

"With over $14 trillion debt already, we should not allow Washington’s big spenders to put us further in the hole. We must get our fiscal house in order with real spending cuts and with real structural reforms that stop the spending spree before it bankrupts our country," he said.

Even the conservative Heritage Foundation, which heralded Ryan's plan as "a monumental budget proposal for monumental times," dinged it for insufficient levels of defense spending and for not addressing Social Security.

Former Massachusetts Gov. Mitt Romney commented on the plan later in the day.

"I applaud Rep. Paul Ryan for recognizing the looming financial crisis that faces our nation and for the creative and bold thinking that he brings to the debate," Romney said in a statement. "He is setting the right tone for finally getting spending and entitlements under control."

"Anyone who has read my book knows that we are on the same page," Romney said.