US President Barack Obama Thursday bemoaned a "sledgehammer" last decade of economic irresponsibility, but insisted his policies were succeeding in powering a genuine recovery.

Obama launched a two-day western political swing by touring a plant which makes electric vehicles, a symbol of his plan to spend billions of stimulus dollars to develop a new job-rich green energy revolution.

"This recession was the culmination of a decade of irresponsibility -- a decade that fell like a sledgehammer on middle class families," Obama said, blaming the worst slump in decades partly on the last Republican administration.

Obama, who has seen his personal approval ratings slide as fears grow that the recovery may be slowing, said he had taken necessary decisions to rescue the recovery, even though they were unpopular.

"What is absolutely clear is that we are moving in the right direction -- the surest way out of this storm is to go forwards not to go backwards.

"There are some people who argue that we ought to abandon our efforts - and some people who have made the political calculation ... that it's better to obstruct than lend a hand," Obama said in a swipe at his Republican critics.

"But my answer is ... come right here to Kansas City."

The president toured Smith Electric Vehicles, a firm that won 32 million dollars in funding from his stimulus package to build electric trucks and has so far created 50 jobs and has ambitious expansion plans.

Obama argues that the United States must revolutionize its economy and produce new green jobs to wean the United States off foreign oil, create jobs win a battle with competitors abroad and to ease environmental damage.

His visit to Missouri and Nevada was designed to drive home his message of economic recovery, and fill campaign coffers ahead of November's elections.

As well as his visit to the Smith Electric Vehicles plant he will headline fundraisers for Missouri Democratic Senate candidate Robin Carnahan, as he cranks up the pace of campaigning ahead of crucial mid-term congressional elections in November.

Obama then moves on to the gambling paradise of Las Vegas, Nevada, to support embattled Senate Democratic Majority leader Harry Reid, who is facing a tough reelection bid and is the top election target of the Republicans.

Democrats fear that the mid-term polls, in which all of the House of Representatives and a third of the Senate are up for grabs, could challenge their monopoly on power in Washington.

Voters often use first-term mid-term elections to send a rebuke to new US leaders, or to make a course correction after previous presidential elections.

In recent days, Obama has been trying to talk up the US recovery, and to remind voters of the parlous state of the economy when he took office last year, amid the deepest economic crisis since the 1930s.

He touts the creation of 600,000 private sector jobs so far this year and says the economy is now well on the road to recovery.

Yet his political prospects are being clouded by unemployment running at 9.5 percent, the fact that many Americans do not yet feel the recovery, and official data that has sparked fears the rebound is slowing.