UNDER slate grey skies in the car park of a tyre factory in northeastern Ohio, a group of union officials and workers were plotting last week their own small but significant part in the attempted overthrow of the US Republican political ascendancy.

This year the Denman Tyre Company, one of America’s last surviving independent manufacturers, made 50 redundant at the 350-worker Leavittsburg plant. To survive in a global market the company makes tyres overseas at labour costs a fraction of what the unionised staff make in Ohio. It was not the first round of redundancies and few of the employees think this year’s will be the last.

The smell of burning rubber from the plant mingled with the aroma of strong coffee as the men and women gathered last week with Sherrod Brown, the Democratic candidate for the Ohio Senate seat in November’s election — the man they hope will help to end years of Republican domination of American politics. Still in his early 50s, Mr Brown has been in Ohio politics for 30 years, the last 14 as a member of the House of Representatives. Stooped slightly, as though he carries the weight of all Ohio’s economic hardships on his shoulders, he works the workers and their families, and shaking his head at tales of the follies of global capitalism.

He is scathing about the economic damage he says has been done to his state. Republicans have got rich, he says, while they have shipped jobs overseas. His opponent, Mike De Wine, the incumbent senator, has taken campaign money from companies that are destroying American jobs. “Why should we reward companies that move offshore to avoid US taxes?” Mr Brown asks. “We need fair trade, not free trade.”

This autumn Ohio is again the central battleground of US politics. It was the state that gave President Bush his narrow victory over John Kerry in 2004. Now it is one of half a dozen states that Democrats need to win on November 7 to take control of the Senate and pave the way, they hope, for an era of Democratic control.

Polls suggest that Mr Brown is narrowly ahead in his attempt to become the first Democratic senator here since John Glenn, the former astronaut, who retired in 1992. The unpopularity of the Iraq war has undermined Republicans in the state. But in a reminder of the broader political headwinds the governing party is fighting, at least as big an issue for Ohio voters is the economy. Democrats here and in much of the country are hoping to channel voter anger over the economy into a winning message.

At first sight this seems odd. The US has for five years enjoyed a period of strong growth. Unemployment nationally is less than 5 per cent — low by any historical standards. But in much of the nation this good news is eclipsed by the fear that the global economy is destroying good jobs and replacing them with low-wage service sector employment.

Household income for the average middle-income American family rose a little last year, but that was the first increase in six years. In real terms, median incomes have not climbed back above where they were in 1997. Gary Steinbeck, of the local branch of the United Steelworkers’ Union, says that the workers who are left at Denman have not had a cost-of-living pay increase since 1988. “Since we last had a Democratic senator we’ve lost 300,000 jobs; good paying, manufacturing jobs,” he adds.

Ohio offers an intriguing hint of the future of the Democratic Party and the polarised nature of American politics.

Mr Brown is an old-fashioned economic populist. In a career in politics he has not, unlike some of his colleagues, enriched himself. He is unashamedly a liberal, American political-speak for a leftwinger. He voted against the Iraq war and is scathing about President Bush’s War on Terror. But it is in economics that Mr Brown’s liberal credentials are most evident. He has voted repeatedly against trade agreements in Congress. Bill Clinton was wrong, he says, to support Nafta, the North American Free Trade Agreement, and other trade deals.

Mr Brown is sponsoring the Patriot Corporations Act, which would reward companies that keep jobs in America with tax breaks. He says US jobs must not be put in peril because of trade agreements with countries that do not treat workers fairly. All of which suggests a Democratic political ascendancy might create its own problems for the rest of the world. The Republicans have been attacked by the Democrats for pursuing a go-it-alone approach to threats to the nation’s security. But the Democrats, if Mr Brown is any guide, seem just as eager to take the US down a similar path in the face of perceived threats from the global economy.

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