Liberals were on the verge of revolt as Obama refused to say any final deal must include a government-run insurance option, while Republicans pressed their all-but-unified opposition to the White House effort. Obama, who was to leave Washington today on vacation, said reason would prevail and it was no time to panic.

"I guarantee you . . . we are going to get health-care reform done. And I know that there are a lot of people out there who have been hand-wringing, and folks in the press are following every little twist and turn of the legislative process," Obama told a caller to Philadelphia-based radio talk show host and Philadelphia Daily News columnist Michael Smerconish during a broadcast from the White House.

Opponents of the overhaul have drowned out supporters at lawmakers' town halls around the country this month, and public backing for Obama's effort has slipped in opinion polls.

"I said during the campaign that the best offense against lies is the truth," Obama said. "And so all we can do is just keep on pushing the truth."

On the Smerconish show, Obama also said the Libyan convicted in the Pan Am 103 bombing over Lockerbie Scotland and freed yesterday by Scottish authorities should be placed under house arrest in Libya. Thousands greeted Abdel Baset al-Megrahi in Tripoli in a festive atmosphere.

The Scots said that al-Megrahi was being released because he is terminally ill. The bombing killed 270 people, including 189 Americans.