Barack Obama has been here before — politically endangered, doubts mounting about his leadership, and a growing sense that, for all his promise, he has lost his way.

As he has done before — whether to salvage a candidacy or revive a policy — Obama will resort to a device that has been successful for him in the past: the Big Speech.

With most of the country saying he has mismanaged the economy, President Obama will use an address to a joint session of Congress on Thursday to outline his plan to create jobs and head off a second recession. It will be the fifth time Obama has spoken to a joint session, the howitzer of the presidential communications arsenal.

But the risks this time are as high as the potential for any reward.

Obama faces some particular challenges on this outing, ones magnified by the summer’s debt-ceiling debate, when he spoke frequently to the American public but with little effect on the outcome.

Americans have been hearing a lot from him. For months, he has discussed some of the same jobs proposals he will detail in the speech, mentioning them as recently as this week at a Labor Day rally in Detroit.

With the unemployment rate locked in above 9 percent, voters are weary of words. Another high-profile speech is likely to underscore how little has changed since Obama said in his first joint-session address, a month after taking office, “Now is the time to jump-start job creation.”

Beyond the specific policy prescriptions, Obama’s speech will also serve as an opening statement of his reelection bid, the success of which may depend on his ability to persuade a divided Congress to act on his proposals — or saddle it with the blame if it refuses to go along.

“He better be prepared to say something that people haven’t heard before, or it’s going to be counterproductive,” said Stephen Hess, a senior fellow at the Brookings Institution. “In many ways, he’s run out of options, at least the options that you’d want to advertise before a full-blooded, joint session of Congress.”

Even some of his critics grant that Obama is a gifted orator and that he has used the big speech effectively to get himself out of political trouble before.

During a neck-and-neck Democratic primary campaign in 2008, Obama spoke to the nation about the legacy of race in America, largely clearing the issue from the contest and reinvigorating his campaign. After the summer of 2009, when angry anti-health-care town hall meetings emerged as a fixture on the political landscape, he urged a joint session of Congress to reform health care, putting the initiative back on track.

His December 2009 address at the U.S. Military Academy at West Point, where he outlined both an escalation of the unpopular Afghanistan war effort and an exit strategy, clarified his policy after a months-long internal debate that his critics called dithering. Polls recorded a rise in support for the war, albeit a temporary one.

Poll numbers loom

Thursday evening, Obama will again address an American electorate with doubts about his presidency.

A Washington Post-ABC News poll published this week found that 60 percent of those surveyed disapprove of the way Obama has managed the economy and that only 43 percent approve of the job he is doing overall. That is the lowest rating of his presidency.

Obama will be trying to change the perception that he is a weak and rudderless leader. The sharply partisan debate this summer over how to raise the debt ceiling deepened that impression among some people, who saw him trying mightily, but ultimately unsuccessfully, to resolve the conflict.

When it ended, many Democrats believed Obama had acquiesced to Republican budget-cutting demands to get to a resolution.

Obama and his advisers, though, are betting that voters, especially young ones, will support a reelection strategy that presents him as a post-partisan president, more interested in problem-solving than ideology.

His advisers say the speech will seek to inject a new sense of urgency into the economic debate and challenge Congress to act or be blamed for not doing so.

But his Republican critics say Obama is raising expectations too high by choosing to address a joint session of Congress.

“The pressure on the president to really come with something in that speech is much greater than it should have been,” Sen. Roy Blunt (R-Mo.) said Wednesday. “There’s lots of venues,” Blunt added. “The House of Representatives before joint session of Congress establishes a high expectation.”

In response, Jay Carney, the White House press secretary, told reporters Wednesday that Obama will “do it in front of Congress because he is calling on Congress to act.”

“Do you really think outside in the country that Americans think we’re raising expectations too high because we think the American economy is the most important subject to talk about right now? I don’t think so,” Carney said, “We believe it’s imperative for Congress to act. We believe the American people are demanding that Congress act and pay for its actions.”

It is a blame-Congress strategy that has been successful before.

Presidential precedent

In July 1948, President Harry Truman addressed a joint session of Congress on the need to act against rising inflation, outlining a series of steps it should take immediately to prevent “another Great Depression.”

The following month, Truman issued a status report detailing congressional action on his economic plan, using the phrase “failed to act” more than a dozen times. An underdog, Truman won the election a few months later.

“He knew they weren’t going to do it, so it strengthened his ability to attack them as the do-nothing Congress,” said Robert Dallek, the author and presidential historian. “I see a certain parallel here.”

Dallek called a presidential speech “a powerful instrument of opinion-making and influence.” But he acknowledged that, for Obama, the address to Congress may be all he has left to shape public opinion about his economic record.

Not all of Obama’s big-speech attempts have been successful.

A month after his inauguration, Obama outlined for a joint session of Congress “an agenda that begins with jobs.” Eight months later, the unemployment rate had climbed to a peak of 10.2 percent, more than two percentage points higher than when he spoke.

Carney said that while Obama understands there are other ideas in circulation about how to improve the economy, he will urge Congress to pass his proposals because “they are sensible, they are bipartisan and they are paid for.”

He suggested that the White House chose the big-speech option because direct negotiations with Congress, House Republicans in particular, have been of limited value.

“I do not believe that anyone out there in the country thinks that the answer to getting Washington out of gridlock is having another round of meetings in the Cabinet Room,” he said.