WASHINGTON -- Defending a costly plan to revitalize the economy, Vice President Joe Biden on Thursday said the government's sweeping stimulus effort "is in fact working" despite steady Republican criticism and public skepticism. 

"The recovery act has played a significant role in changing the trajectory of our economy, and changing the conversation in this country," Biden said. "Instead of talking about the beginning of a depression, we are talking about the end of a recession." 

Nearly 200 days into the effort, Biden delivered an upbeat report card about the $787 billion rescue effort that President Barack Obama pushed through Congress. He quoted estimates by private analysts that the plan has created or saved 500,000 to 750,000 jobs so far. But many million people remain out of work. 

The effectiveness of the two-year program is a matter of sharp political debate, and Biden sought to counter critics with a listing of tangible results. 

"One of the criticisms is that it is simply a grab bag of different programs," Biden said in a speech at The Brookings Institution. "But the fact that the recovery act is multifaceted doesn't reflect a lack of design, it is the design." 

The stimulus package is a mix of tax cuts, increased spending on Medicaid and huge investments in infrastructure, education, energy projects and more. 

The White House is eager to promote signs of progress as the economy lumbers out of recession. 

Many economists warn that the unemployment rate will keep rising until at least next summer, and it is that measure -- the loss or creation of jobs -- by which many Americans decide whether economic life is getting better. 

Obama's Council of Economic Advisers on Sept. 10 will report an updated projection of the number of jobs created or saved because of the stimulus plan. Biden said he expected it will back up his predictions of 150,000 jobs in the first 100 days and another 600,000 formed or saved over the second 100 days of the act. 

Biden warned that the recovery will be uneven. But he said so far, the law is "doing more, faster, more efficiently, and more effectively than most expected." 

The White House, though, has also admitted that its initial economic forecasts to sell the stimulus were too rosy. Many Republican leaders say the stimulus is not working nearly as well as the White House promotes, and at huge cost of debt to the nation. 

With Obama on vacation at the Camp David presidential retreat in Maryland, the White House hopes Biden's message will break through. 

A Gallup poll last month found 51 percent of Americans wished the government would have spent less to stimulate the economy. The same poll found 41 percent thought the stimulus package was helping the economy in the short term; 33 percent saw no effect, and 24 said it was making the economy worse. 

The vice president's appearance is part of a concerted White House push in advance of the 200th day of the stimulus act on Saturday. Five top administration officials plan to speak about the law's benefits on Thursday in appearances in Arkansas, Virginia, Illinois, California and Minnesota. 

Public approval of Obama's performance and of his handling of the economy have slipped. Polls now put both figures slightly above 50 percent.