WASHINGTON (AFP) - President Barack Obama on Wednesday launched a ground campaign to defend his vision for the United States economy, vowing to revitalise the American middle class in the face of a hostile Congress.

Mr Obama made a robust defence of his stalled economic initiatives, which have been bottled up in the Republican-led House of Representatives - the branch of Congress responsible for managing the nation's checkbook.

The President planned to visit three US cities over two days, for a series of addresses on accelerating economic growth and creating jobs.

The speeches, which come six months into his second term, started on Wednesday at Knox College in Galesburg, Illinois, which he first visited as a newly elected senator eight years ago. Mr Obama told the crowd in his adopted home state that generations of middle class prosperity had begun to stall, in recent years, leaving the economy hamstrung.

"By the time I took office in 2009, we all know that the bubble had burst, costing millions of Americans their jobs, their homes, and their savings," the President told the crowd. "The decades-long erosion of middle-class security was laid bare for all to see and feel."

But, Mr Obama continued: "Today, five years after the start of that Great Recession, America has fought its way back."

The President told the crowd that his administration helped to begin the rescue of the nation's economic stagnation, rescuing the auto industry, revamping the health-care system and shoring up the financial sector, among other achievements.

"Thanks to the grit and resilience of the American people, we've cleared away the rubble from the financial crisis and begun to lay a new foundation for stronger, more durable economic growth," he said.

But the President's efforts to reframe the debate over the economy comes with Congress reloading for a new round of battles over raising the debt ceiling and other economic fights.

Mr Obama and Republican lawmakers are bracing for renewed clashes over spending and the federal budget, which threaten to hurt an economy finally showing signs of stabilising after tumbling into a deep economic trough.

Republicans have dismissed Mr Obama's focus on the economy as a thinly veiled excuse to seek more spending.

"If the President was serious about helping our economy, he wouldn't give another speech, he'd reach out and actually work with us," House Speaker John Boehner said on Tuesday.

Mr Obama hopes to negotiate a new fiscal compromise by October - the end of the current fiscal year - in order to head off the threat of a government shutdown that could further damage the sluggish recovery.

After Wednesday's speech in Illinois, Mr Obama was to give an address later in the day at the University of Central Missouri, in Warrensburg. On Thursday he heads to Florida, where he will give a speech at the Jacksonville Port Authority.

Since his last speech in Galesburg, the US suffered its worst economic crisis in two generations before a halting recovery finally began to take hold.

He added, however, that there is still a ways to go for the economic rebound to solidify.

"We're not there yet. We all know that," Mr Obama told the crowd. "We've got more work to do."