The line snaked down the middle of Columbus for over a mile, old white ladies dancing to Aretha Franklin, young black men hugging them, toddlers clutching Yes We Can! banners: a big, feel good, central Ohio Barack Obama love-in hiding bags of last-minute nerves.

Many had walked for miles to attend one of the Democratic candidate’s final rallies in the heart of this crucial battleground, clad in a dazzling array of Obama clothing that could fill a fat catalogue: there were T-shirts proclaiming ‘Hope!’ and ‘Change!’, ‘Obama ’08: Mission Impossible‘, ‘Together We Stand’, ‘Obama, the Next President’, ‘I Love Obama’, and simply: ‘YES’.

By the time Mr Obama walked down the Ohio statehouse steps at 1.30pm, clutching the hands of his daughters Sasha and Malia, the huge crowd was roaring and whistling and whooping, chanting “O-BA-MA” and “Yes We Can!” A grey-haired octogenarian jigged to Bruce Springsteen’s ‘The Rising’ as it thumped from giant loudspeakers. “I am overwhelmed by this crowd,” Mr Obama declared. “It’s unbelievable. Ohio, I have just two words for you: two days!”

Yet beneath the energy and party atmosphere - it was the biggest political rally in Columbus’s history - and the heady excitement that after this marathon presidential campaign they had at last reached the cusp of history, many of these Ohions were suffering a new mental condition on the eve of Election Day. It could be called Victory Will Still Be Snatched From Us Compulsive Disorder.

“I am so afraid some ghastly trick will be played again and we’ll wake up on Wednesday morning and we’ll be where we were in the last two elections,” said Stephanie Harper, 32, as she walked towards the rally with thousands of others. “My doctor says she is treating lots of Democrats for anxiety and depression, because of their obsession with this election and their fears that Obama will lose.”

Like Florida Democrats, who will never be dissuaded that the 2000 race was not stolen from them, their counterparts in Ohio still believe - without compelling evidence - that John Kerry was robbed of the presidency in 2004 because of Republican dirty tricks on voting day here. If the Democratic nominee had won 60,000 more votes in the Buckeye State four years ago, he would be in the White House today.

Alec Clairmont, 23, described himself as “extremely nervous”, and was muttering darkly about a documentary he had seen the night before alleging that “people can programme voting machines so that they can send votes to other side”. He added: “The polls look good but I don’t know what will actually happen on Election Day.”

Wearing a shirt declaring ‘Another Old White Woman for Obama’, Annie Horner, 63, said anxiety levels were intense, but she was telling her friends who were worried “not to put all that negative energy out there.” Mr Obama, she said to the strains of U2’s ‘It’s a Beautiful Day’, would be propelled to the White House on a wave of “positive energy”.

Mr Obama and his aides are taking a somewhat less holistic approach in these last hours. They realise that the road to the White House runs through Ohio and its 20 Electoral College votes, and have put in place an eleventh-hour get-out-the vote operation that is brutal in its scale and intensity.

This election has been going on so long, and living rooms have been filled with so many television pundits pouring over electoral maps, that children born when Mr Obama declared his candidacy can probably recite today the reasons why Ohio is so important.

No Republican has ever won the White House without it. From 1904 to 2004, the Ohio victor won the presidency 24 of 26 times. Only two Democrats - Franklin D Roosevelt in 1944 and John F Kennedy in 1960 - won the presidency without carrying Ohio. Four years ago, President Bush beat Mr Kerry here by two points - delivering his re-election.

Yesterday’s visit by Mr Obama, the first of his final six rallies of his two-year White House quest, was his 33rd visit to Ohio since September 5; Mr McCain has made 28 during the same period. It has been the most visited state by the candidates, and if the Republican loses here tomorrow, his presidential hopes will almost certainly be ended.

Aides to both candidates agree that Ohio remains extremely close. After his rally in Columbus, Mr Obama was due to hold two more events here, including an appearance with Mr Springsteen in Cleveland.

“I don’t know what else to say,” Michelle Obama, the candidates wife, told the crowd as she introduced him. “It’s been a long journey. It’s been an amazing journey.”

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