Only one store prospers on Main Street in Chillicothe, a town of 22,000 people on the edge of the Appalachian mountain region in Ohio whose venerable public buildings speak of a happier past. It is Frank’s Pawn Shop.

Gary Jacobs, its manager, stands amid the guns, guitars and jewellery brought in by locals. He said: “Right now people would just about sell the shirts off their back.” A customer called Cindy, who works in a prison, chipped in: “Look at me. They own half my stuff. We’re broke. We need a change and we need it quick.”

The town’s largest employers — a truck factory and a paper mill — had shed nearly 1,000 jobs even before the Wall Street meltdown. Figures released on Friday showed local unemployment has reached 8.6 per cent. Food and fuel prices have surged. The value of retirement funds has plummeted. ‘For sale’ signs are everywhere, and the Chillicothe Gazette has already run 280 property foreclosure notices this year.

In three hours, The Times met four Chillicothians like Cindy who backed President Bush in 2004 but now favour Barack Obama — an ominous sign for John McCain because in the past two elections Chillicothe’s vote has precisely mirrored the finely balanced statewide vote.

Indeed, polls suggest that Mr Obama is finally pulling ahead in a state that Mr McCain simply has to win — no Republican has ever captured the White House without Ohio. One survey last week gave the Democrat an eight-point advantage. Another in yesterday’s Columbus Dispatch showed him leading by 49 to 42 per cent with only 8 per cent undecided, and tens of thousands of Ohioans are already casting absentee ballots.

However much Mr McCain tries to distance himself from the Bush Administration, observers say the Wall Street meltdown — and his erratic response— has hurt him in an industrial state that has lost 236,000 jobs since 2000, suffered nearly 30,000 foreclosures and endured the worst economy in America after neighbouring Michigan, where he ceased competing last week.

Joe Hallett, the Dispatch’s senior editor, said: “The Wall Street debacle has really turned the tide.” Herb Asher, a political science professor at Ohio State University, added: “Obama has the momentum. It’s the economic issues of the past two weeks.”

If Mr Jacobs’s pawn shop embodies Mr McCain’s political problems in Ohio, a man called Ronald Stephenson demonstrates the other big challenge the Republican faces in a state where a party’s ability to turn out its supporters is often decisive.

Mr Stephenson, 41, was released from prison in June after serving 13 years for rape. He now lives in the Faith Mission men’s shelter — a stark, brick building in a rundown neighbourhood near downtown Columbus, the state capital. He is not usually sought after, but last week Obama supporters drove him across the city to the Veterans Memorial convention centre to register and vote.

The Republicans have long had a formidable get-out-the-vote machine in Ohio. That is how Mr Bush won the state by 118,600 votes four years ago and clinched his re-election. But now, says Mr Hallett, “Obama is without question better organised”.

Over the past week his supporters have ferried to the state’s 88 absentee voting centres thousands of denizens of homeless shelters and soup kitchens, students, members of black churches and other groups seen as natural Democrats. They have enlisted hundreds of barbers’ shops and beauty salons in Ohio’s black neighbourhoods to recruit voters. They have even cajoled prison imates awaiting trial to register for absentee ballots.

They are fully exploiting a hotly contested rule change permitting first-time voters to register and vote simultaneously during the one-week overlap between the start of absentee voting last Tuesday and tonight’s deadline for voter registration. They have shipped in Bruce Springsteen, Jerry Springer, Russell Simmons, the hip-hop pioneer, James P. Hoffa, the Teamsters’ union leader, and other big names to lead get-out-the-vote rallies. They hired a plane to fly a banner over the 100,000 spectators at an Ohio State University football game.

Mr Obama has 77 field offices and 300 full-time staff across the Buckeye state — far more than Mr McCain, who is relying on a battle-hardened army of volunteers. He is contesting all 88 counties whereas John Kerry, the Democratic nominee in 2004, organised only in the ten largest. He has the invaluable backing of Ted Strickland, a popular Democrat who won the governorship in 2006, and studies suggest that most of the 700,000 new voters registered in Ohio since December are Democrats.

But for all this, Mr Obama has yet to “seal the deal”, as one Republican official put it. Hillary Clinton carried 83 of Ohio’s 88 counties in March’s Democratic primary despite being outspent two to one by Mr Obama, and as a Harvard-educated big-city liberal he has found it hard to gain traction among the working class whites of the state’s northeastern rustbelt and Appalachian southeast.

Then there is the intractable issue of race. Obama can expect a record black turnout but however bad the economy there is a significant number of white Ohioans, particularly in rural Appalachia, who would never vote for a black candidate. Mr Jacobs, the pawn shop manager, freely admitted he was one of them. “I don’t think the US is ready for a black president,” he said bluntly.

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