Mr. Paulson said on Friday that the problems were spawned by shaky and sometimes opaque real estate investments, driven by irresponsible lenders and borrowers. Now, he said, vital streams of credit have been clogged, not just for big investors but also for families wanting to buy houses and cars and pay for tuition.

Image Treasury Secretary Henry M. Paulson Jr. discussed the latest actions to restore confidence in the markets on Friday in Washington. Credit... J. Scott Applewhite/Associated Press

But if what Mr. Paulson told the lawmakers was similar to what he told the American public on Friday, he surely conveyed to them a sense of urgency, telling the legislators that the situation was too important for them to adjourn and go home to campaign, which many of them hoped to be doing by now.

President Bush and Mr. Paulson appealed for a bipartisan approach. The president described this as “a pivotal moment for America’s economy” and appealed to the collective resilience of the American people, which he said had sustained them over the last seven years through terrorist attacks, economic downturns and natural disasters.

“We will weather this challenge too, and we must do so together,” Mr. Bush said. “This is no time for partisanship.”

House Speaker Nancy Pelosi, Democrat of California, pledged on Friday that the House would act quickly, once it received the administration’s proposal. “As I told the president this morning, we are committed to quick, bipartisan action while ensuring that we uphold key principles  insulating Main Street from Wall Street and keeping people in their homes by reducing mortgage foreclosures, restoring market confidence and protecting American taxpayers from incurring hundreds of billions of dollars of debt,” Ms. Pelosi said in a statement.

Many members of Congress were looking forward to going home next week to campaign, but Ms. Pelosi said the legislators were prepared to stay in Washington if necessary to address “this historic crisis.”

What Mr. Paulson called the “tactical steps” taken by the government caused the markets to shoot up on Friday morning. But deeper, long-range moves are necessary to address the causes of the crisis, he said.