Mitt Romney, the Republican presidential hopeful, sharpened his focus on economic issues on Wednesday after winning the Michigan primary with a promise to fight for US jobs and revive failing industries.

The former governor of Massachusetts said his Michigan campaign message would resonate throughout the US as fears grow that the economy is heading for recession.

“I think you’re seeing people across the country very concerned about the economy,” he told CBS. “They want somebody who understands how the economy works, who knows why jobs come and why they go.”

Mr Romney beat John McCain, senator for Arizona, in Michigan after a campaign dominated by the state’s deep economic malaise.

At his victory rally on Tuesday night he declared his win a triumph for optimism over “Washington-style pessimism” – referring to remarks by Mr McCain that some lost jobs “are not coming back” to Michigan.

Mr Romney was aided by his family ties to Michigan, having spent the first 18 years of his life there as the son of a popular three-term state governor. His father’s background in the car industry also helped him appeal to voters worried about the loss of jobs from the state’s biggest employer.

On Wednesday, he vowed to take his economic message nationwide as the focus shifted to forthcoming primaries in South Carolina, Nevada and Florida.

“I came in and said, ‘Look, I'm going to fight like the dickens to try and help the [car] industry and turn this state around, and frankly, I’m going to try to turn the nation’s economy around as well,” he told MSNBC. “I don’t want to see any jobs leave this great country.” 

Mr Romney has portrayed himself as the most qualified candidate to revive the economy and shake up Washington, pointing to his two decades of experience in the private sector as co-founder of Bain Capital, the private equity company, and his success in rescuing the 2002 Salt Lake City Winter Olympics from financial crisis.

The emphasis of the multimillionaire’s campaign on economic issues responds to the growing recession fear among the electorate. A Reuters/Zogby poll on Wednesday showed 47.5 per cent of voters think a recession is likely in the next year, up from 43.4 per cent in the previous month’s survey.

However, the pollster John Zogby said an economic-focused presidential campaign would be difficult for Republicans because many voters blame George W. Bush’s administration for the downturn.

“We’re no longer waiting for the economy to be the No 1 [election] issue. It is far and away the issue,” he said. “Democrats have a very simple message on the economy: ‘It stinks. It’s Bush’s fault.’ A Republican can’t say that.”

When asked which presidential candidate would be best for respondents’ financial situation, 20.1 per cent said Hillary Clinton, the New York senator and Democratic frontrunner, and 13.6 per cent chose Barack Obama, her main Democratic rival.

Mr McCain was the top ranked Republican, with just 10.9 per cent.