Obama crowds flock to Chicago razzle dazzle

The world's most powerful nation began voting at 6am to deliver its verdict on the two-year contest between Barack Obama and John McCain, seen by many as the most electrifying duel since JFK v Nixon.

Today's opinion polls suggested a slight widening of Mr Obama's national lead to 7.5 per cent. His team was confident but some analysts were not ruling out a surprise victory by a dogged Mr McCain, who kept campaigning around the country even after voting started.

Mr Obama, the Illinois senator and now Chicago's most famous resident, will give his first reaction to the result in Grant Park, which has been the scene of a papal mass and pop concerts. Some 70,000 tickets were issued for a central area while tens of thousands more were being allowed in a separate unticketed area. But after warnings that a million supporters were flooding into the area, city officials ordered the police to turn people away if necessary.

In a symbolic boost to his hopes, the tiny hamlet of Dixville Notch, New Hampshire, swung behind him. It opened its polls at midnight in order to be the first to vote and after a 100 per cent turnout of all 21 voters, Mr Obama was declared victor by 15 to six. The village backed George W Bush in 2004.

Riding a wave of resentment against President Bush and over the economic downturn, Democrats were also hoping to make major gains in elections to Congress. They hoped to gain nine Senate seats, giving them a big enough majority to ignore Republican procedural devices that are used to block proposed laws.

The Obama campaign climaxed at a rally early today in Manassas, Virginia - near the site of the first major battle of the American Civil War that ended slavery - where an estimated 70,000 to 100,000 people turned out. He told them: "Whatever happens tomorrow, I have been deeply humbled by this journey. You've enriched my life. You have moved me again and again, you have inspired me, sometimes when I am down you've lifted me up. You've filled me with new hope for our future and you've reminded me about what makes America so special."

Under the US system, the election is fought on a state-by-state basis. Each state is worth a number of electoral votes, depending on its population, and a candidate needs 270 to win.

Early indicators will be Virginia and Indiana, both Republican states in the past, which will be among the first to declare late tonight. "If Obama wins Virginia, he's won the election," said Tad Devine, who worked for Democrat candidates John Kerry and Al Gore. "It says Obama was able to do something we only dreamed of four years ago."

At the end of his campaign tour, MrObama told reporters on his plane: "OK, guys, let's go home. It will be fun to see how the story ends." He was planning a game of basketball to relax while waiting for the polls to close.

Mr McCain, appearing on breakfast television, said he had no regrets: "It's been one of the most incredible experiences that anyone can have. I've loved every minute of it."