(CNN) -- President Obama appeared before a national audience Monday night to make the case for his economic stimulus plan, saying this is not your "run-of-the-mill recession."

President Obama urged Congress "to act without delay" on his economic stimulus plan.

The president stressed the urgency of passing the roughly $838 billion measure, which his administration and Democratic leaders say will help pull the U.S. economy out of its current skid.

"My bottom line is to make sure that we are saving or creating 4 million jobs, we are making sure that the financial system is working again, that homeowners are getting some relief," he said in his first prime time news conference.

Obama's remarks came the day before the Senate votes on its version of the stimulus bill. The House passed its version of the stimulus bill nearly two weeks ago -- without a single Republican vote. If the measure passes the Senate, the two chambers will have to reconcile the differences between the two bills. See what's in the bills »

Obama urged Congress "to act without delay," saying that only the federal government can break the "vicious cycle" gripping the U.S. economy.

"It is absolutely true that we cannot depend on government alone to create jobs or economic growth. That is and must be the role of the private sector," he said.

"But at this particular moment, with the private sector so weakened by this recession, the federal government is the only entity left with the resources to jolt our economy back to life."

Obama said the plan was "not perfect," but would create up to 4 million new jobs. Watch Obama explain how the plan will create jobs »

The president said 90 percent of those jobs would be generated by the private sector, a rebuttal of some conservative critics who say the plan amounts to little more than a government jobs bill. How did Obama do? Analysts weigh in »

Much of the package involves infrastructure spending, long-term energy projects and aid to cash-strapped state and local government. The president predicted that with his plan, the country would see significant improvement starting next year.

Republicans opposed to the plan say it includes too much wasteful spending and won't stimulate the economy. Obama insisted he has been consulting with GOP lawmakers on the plan.

The campaign arm of Senate Republicans wasted little time Monday night calling into question Obama's commitment to bipartisanship.

Even before the news conference came to a close, National Republican Senatorial Committee spokesman Brian Walsh released a statement saying, "President Obama promised change and bipartisanship in Washington, but that's not what Americans have witnessed in the crafting of this gargantuan spending bill.

"Despite his rhetoric tonight, President Obama cannot possibly be proud of the final result -- a bloated, trillion dollar spending bill crafted in a partisan manner that represents the same wasteful Washington spending and will fall on the shoulders of future generations."

Obama said that when it comes to fiscal responsibility, "it's a little hard for me to take criticism from folks about this recovery package after they've presided over a doubling of the national debt." Watch Obama take on his critics »

Obama also addressed a broader argument -- that the government should not be trying to fix the problem.

"You have some people, very sincere, who philosophically just think the government has no business interfering in the marketplace. And, in fact, there are several who've suggested that FDR was wrong to interfere back in the New Deal. They're fighting battles that I thought were resolved a pretty long time ago," he said.

The president said most economists "almost unanimously" recognize the government needs to play a role in jump-starting the economy.

Obama said he was "absolutely confident" the country's economic problems can be solved, "but it's going to require us to take some significant, important steps."

Obama pointed to Japan to back up his claim that without action, the recession could become permanent.

"We saw this happen in Japan in the 1990s, where they did not act boldly and swiftly enough and, as a consequence, they suffered what was called the lost decade, where essentially, for the entire '90s, they did not see any significant economic growth."

The Obama administration says the plan will spur job creation and long-term growth by:

Doubling the production of alternative energy in the next three years

Modernizing federal buildings and improving the energy efficiency of 2 million American homes

Making investments to have the country's medical records computerized within five years

Equipping schools with 21st-century classrooms

Expanding broadband access

Investing in science and new technologies

Obama road-tested his message about the plan Monday in Elkhart, Indiana.

He is planning a second campaign-style swing Tuesday, heading to Fort Myers, Florida, another city wrestling with double-digit unemployment.

Polls show the public is split over the stimulus plan. A slight majority, 54 percent, favors the bill; 45 percent are opposed, according to a CNN/Opinion Research Corp. survey released Monday. iReport.com: Can Obama fix the economy?

The president wants the final bill on his desk by Presidents Day, which is next Monday.

As Obama pushes for the stimulus plan, his administration also has been planning a separate financial stability plan for the second half of the $700 billion financial bailout program.

"Clear oversight" will be required for the remaining funds, Obama said.

Treasury Secretary Tim Geithner is scheduled to announce a substantial overhaul of the bailout Tuesday. The program, launched by the Bush administration, has come under fire for its lack of transparency.

While the economy was the focus of the news conference, Obama also fielded questions on foreign policy.

On Iran, he said the United States is looking for opportunities for "face to face" dialogue after nearly three decades without diplomatic ties, but still has "deep concerns" about Tehran's actions. Watch Obama discuss talks with Iran »

He said Afghanistan "is going to be a big challenge," and that his administration would have to work "smartly and effectively" to prevent al Qaeda safe-havens in the region. He said he had no timetable for how long that would take. Watch what Obama says about Afghanistan »

Obama took questions from 13 different reporters in his first prime time news conference. Eight questions were about the economy, three were about foreign policy and one was about creating a truth and reconciliation committee to investigate the Bush administration.

CNN's Ed Henry and Mark Preston contributed to this report.

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