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In the North Denver Democrats' staging post the tables and chairs have already been dismantled, the 8 ft by 4ft Obama-Biden sign already taken off the wall. But with half an hour to go before polls close, we still have work to do.

"Whoever doesn't have a phone needs to get calling, " orders our phone captain, standing in the middle of the room. We can't give up until they tell us Colorado is won although with Pennsylvania gone and the Senate falling, we all know what is happening here tonight.

As an old, crackly television slowly covers the map of America blue, the talk amongst us, the Obama volunteers of Denver, has changed from "When are the results out?" to "Where's the party at?"

Then, at 7:05pm, five minutes after the polls close and an hour after dark, Suzy Lippmann and Eric Sween return to base – the last canvassers to check in. They have just gained one of the last votes of the Colorado election.

Knocking on doors in one of the poorer districts of Denver, they found an 84 - year-old woman who had still not voted. That was 6:10pm.

"She had always voted Democrat, was excited about the election, and wanted to see Obama in office," Ms Lippman explained over a celebratory beer. "But she didn't have a car, she couldn't walk without a cane, and was worried that her sight would not be good enough to fill out the ballot without making a mistake."

Both campaigns have access to fleets of cars, but whether or not volunteers for a political campaign can help someone fill in a ballot raises more problematic questions. "We told her that we would return in 20 minutes and help her out," Ms Lippman said. "When I phoned the office they were worried it might be a problem, but we ignored them, and took her to the polls – where they let me help her."

It took another 20 minutes for them to fill in the ballot, and they left the polling station at 6:55pm.

"It was so inspiring," Ms Lippman said. "She told us she has 9 children, 40 grandchildren and 30 great-grandchildren. They all call her 'Crazy Grandma', because she always talks to them about the news and tells them all to vote. And, without us, she wouldn't have made it."

Eight years ago, the election in Florida dispensed forever with the idea that an individual vote is worthless. Today, the heart of the Democrat strategy was to get out the vote – whatever the cost. And today that strategy paid off.

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