WASHINGTON - A high-stakes White House summit that opened Thursday with Republicans urging President Obama to "start over" on reforming the nation's health care system quickly bogged down into a debate over how to rein in spiraling health care costs.

"We have a very difficult gap to bridge here," said Rep. Eric Cantor, the No. 2 House Republican said in reference to Democrats' stalemated legislation to extend coverage to more than 30 million people who are now uninsured.. "We just can't afford this. That's the ultimate problem."

But Obama and Democratic leaders cast the reform they want as critical to tackling an issue that is even more pressing to many Americans -- the struggling economy.

The apparent strategy for Democrats was to highlight the several points of agreement on health care reform with Republicans and argue that it made no sense to start over again as Republicans are urging...