The legal victory for the Republicans came in the early hours when federal judges ruled that the lower district courts had exaggerated the potential for intimidation.

"The district courts have found a possible chamber of horrors in voting places throughout the state of Ohio based on no evidence whatsoever, save unsubstantiated predictions and speculation," argued judge James Ryan in his written opinion.

By last night, there had been few accounts of intimidation, but the National Association for the Advancement of Colored People demanded that polls be kept open in a handful of populous counties, with large minorities, where queues were particularly long.

In Toledo, a woman filed a lawsuit on behalf of voters who failed to receive absentee ballots on time, asking they be allowed to cast provisional ballots. A federal judge granted her request.

In the unusually long line that wound its way out of the Kings school in Akron at 7am yesterday, Jodi Delamatre, a Democrat, doubted there would be any chal lengers inside. "This isn't a black neighbourhood so I don't think they'll bother," she said. But half an hour later, as she picked up her punch card, the Republican challenger was there, a bespectacled middle-aged woman smiling benignly.

Inside the booth Ms Delamatre stuck the small pen-like pin hard through the punch card next to Democrat John Kerry and held it down for a long time. "I've got to make sure it counts," she said. "I don't want to leave anything to chance."

George Bush won Ohio by 4% in 2000 and the Republicans have never won an election without taking the state. But over the last four years there have been heavy job losses in manufacturing industry, making it one of the most sought-after swing states and producing one of the most intense efforts to get the vote out. Last night, as the polls closed, Democrats were quietly confident that they would narrowly take the state.

Earlier Susan Aylward was at the Democratic party's phone bank punching numbers and reading her lines. "This election is the most important election in our lifetime," she said. "We know the election will be very close. John Kerry needs your vote as your vote is your voice."

If the people called were receptive, she made sure they knew where their nearest polling station was and asked if they needed a lift. Some expressed exasperation at being called once too often. One woman told another volunteer that Jesus would not want her to vote for Mr Kerry.

Inside the Democratic party headquarters of Summit County, the scene was one of frenetic activity. Kerry staffers paced the floor speaking through headsets while volunteers marched through with bags of bagels and crates of bottled water.

This was the ground war. The shock troops went into the field to perform the "knock and drag" - canvassing door-to-door and then dragging people to the polls. At a pep talk for canvassers, the coordinator tried to keep them focused.

"People may want to talk to you about what's going on," he said. "But that's not what we're here for. It's not about arguing or convincing or anything. It's about who's voted and who hasn't."

Rain-soaked canvassers returned to base only to be sent back out as reports suggested that potential voters, tired of standing in the rain, were returning home without voting.

At Buchtel high school, in a predominantly African American area, a man offered leaflets detailing each local and national Democratic candidate. "Be sure to press down hard," he said. "They say there could be some chads hanging out in there."

Inside the gymnasium the Republican challenger was one of the few white faces to be seen. But those in the queue did not seem much concerned. "I know my constitutional rights," said Lee Harris who is voting for Mr Kerry. "My vote has been counted for the last 35 years and while anything is possible, I'm expecting it to be counted now."