WASHINGTON President Barack Obama will face off today with Republican lawmakers at a bipartisan summit expected to stretch out for six hours on live, daytime television.

Expect them to collide, not come together.

Few say Obama will be able to win Republican support for his proposals, especially for the new plan he brings with him that's larger and more expensive than the ones Republicans have already rejected.

Rather, he heads into the session hoping to transform the debate over health care from a referendum on Democrats' proposals - which he has been losing - into a choice between Democratic and Republican ideas over how to fix a system that both sides say needs fixing.

If he can win that debate in the eyes of the public, he could shore up support in Congress among nervous Democrats and perhaps push through some plan to extend coverage to more of the uninsured and try to rein in soaring costs.

Moreover, he could change the dynamics of the coming elections for control of Congress and give his Democratic Party a better chance to ward off a tidal wave of anger that's been building against them.

Republicans are insisting that Obama start from scratch, a notion the White House rejects. They're unified in opposing the Democratic bills passed last year and have pulled back from more ambitious GOP-backed plans that might have provided a foundation for compromise.

Here's a viewer's guide to today's summit for consumers on issues critical to working families, seniors and businesses:

Working families

Though the cost of health insurance is a worry for most Americans, it's a crisis for the nearly 50 million uninsured and about 27 million who buy their own coverage directly from an insurer. The $1 trillion, 10-year plan Obama and the Democrats have drafted focuses mainly on these two groups.

People with coverage from large employers would get some benefits, such as being able to keep children in their late 20s on the company plan - but wouldn't face major changes unless they lose their jobs or strike out on their own.

People who buy insurance directly, as well as small employers, would be able to pick a plan in a new kind of competitive marketplace offering choices similar to what federal employees and Congress members get. But it wouldn't be a free ride.

Most Americans would be required to carry health insurance and prove it to the IRS.

Obama and the Democrats say their plan would make coverage affordable by providing federal subsidies to help more than 30 million now uninsured. But solid middle-class families may still have to stretch to pay premiums. The help is a lot better for people on the lower income rungs.

Under the plan Obama released Monday - his opening bid at the summit - a family of four making $66,000 would have to pay $6,257 in premiums, close to 10 percent of its income. That's even after receiving $3,000 in federal tax credits.

By comparison, a similar family making $44,000 would pay $2,763 - about 6 percent of its income. The estimates come from the nonpartisan Kaiser Family Foundation.

Most Republicans are opposed to an insurance mandate, although they generally like the idea of allowing 20-year-olds to remain on parental coverage. They want to concentrate on stimulating the private market to provide affordable alternatives.

One idea: allowing consumers in high-cost states to buy coverage from insurers in low-cost areas.

Seniors

Obama says his plan would preserve Medicare benefits and finally close the "doughnut hole" prescription coverage gap, in which seniors have to pay the full cost of their medications.

His plan would gradually shrink the gap, but even when it's fully phased in, seniors would still have to pay 25 percent of the cost of their medications until they hit an upper limit - now $4,550 in out-of-pocket expenses. Again, not a free ride.

Obama's proposal is better than what Senate Democrats passed but not as generous as House Democrats provided.

Republicans say Obama is being disingenuous when he claims no Medicare benefits will be cut. His plan would reduce federal payments to a host of providers, and particularly private insurance plans that about a quarter of seniors have found to be an attractive option.

Government economists have warned the Medicare cuts may be unsustainable, forcing Congress to take them back.

Employers

Although Obama's plan may be better than the status quo for consumers who buy their own coverage, it looks like a major headache for the businesses that employ them.

The president wouldn't require employers to provide coverage, but his plan hits them with a stiff fine if even just one of their workers winds up getting federally subsidized benefits. And Obama significantly increased the fines in the Senate-passed bill that he took as the model for the proposal he's bringing to the summit.

Under the Senate plan, a company with 100 workers that fails to provide coverage would have to pay a fine of $75,000. Under Obama's plan, it would be $140,000 - nearly twice as much.