"The president understands very well that health care spending is a major driver of our deficit and debt problem," Carney said. "He believes … we can achieve those savings in ways that protect the people that these programs are supposed to, and were designed to, support and help."

One proposal in the debt commission's report last year called for reworking Medicare's deductibles and copayments so that most beneficiaries have to pay a share of their everyday bills — cost shifts that in a few years would add up to more than $100 billion in taxpayer savings. In exchange, Medicare recipients would get better protection against catastrophic costs.

There was also bipartisan support for scaling back the tax deduction for workplace benefits, which many economists say would be like putting the entire health care system on a diet. It's strongly opposed by unions, a major Democratic constituency.

And the wild card: curbs on jury awards in medical malpractice cases. Democrats and Republicans have been rigidly divided on the issue, an arm-wrestling match between GOP-leaning doctors and trial lawyers who tend to back Democratic candidates. A deal could lead to a breakthrough in other areas.

Former Senate Majority Leader Tom Daschle said "there is virtually no likelihood" Obama will endorse a voucher plan for Medicare or block grants for Medicaid. But medical malpractice is another story. "He has already said he is open to ideas there," said the South Dakota Democrat, an adviser to Democrats on health care issues.

Obama probably won't drill down to that level of detail on Wednesday. Republicans already laid down their marker.

Later this week, the House will debate a plan by Budget Chairman Paul Ryan, R-Wis., which would fundamentally change government health care programs that touch virtually every family, covering about 100 million Americans.

Instead of Medicare, people now 54 and younger would get a government payment to buy private insurance when they retire. The Medicaid health insurance program for low-income people would be converted into a block grant, allowing each state to design its own program. But the poor would lose the right to coverage under federal law.

Ryan's plan has been praised for its boldness. Even some who vehemently disagree with the specifics have credited the congressman for having the courage to finally start an adult conversation with the American people about the real costs of their health care programs.

Obama's approach would display another attribute that's commonly ascribed to adults: caution. A Medicare remake would probably require a mandate from the voters that neither party can claim.

In normal circumstances, the debt commission's ideas would be considered far-reaching and significant. Compared to Ryan's plan, they're incremental. They leave the big health care programs in place, as well as Obama's overhaul law, which Republicans would repeal.

Obama is also expected to indicate his support for the efforts of six senators who are looking for a deficit deal. In the group: three conservative Republicans, Saxby Chambliss of Georgia, Tom Coburn of Oklahoma and Mike Crapo of Idaho; two moderate Democrats, Kent Conrad of North Dakota and Mark Warner of Virginia; and a liberal Democrat, Dick Durbin of Illinois.

One of the ideas they are considering would trigger the recommendations of the deficit commission, if Congress doesn't meet certain targets for spending, taxes and deficits.

Until now, the Gang of Six has worked in obscurity on what many consider a thankless task with dim prospects. The presidential seal of approval could improve their chances.