EARLY RETURNS in the US presidential election this morning pointed to a strong showing by Barack Obama as television networks projected that he was poised to capture the key state of Pennsylvania, although other battleground states were too close to call immediately, writes Denis Stauntonin Chicago.
As the first polls closed last night, John McCain was quickly projected to win the Republican strongholds of Kentucky, South Carolina, Oklahoma and Tennessee and Mr Obama was heading for easy wins in Vermont, Connecticut, New Jersey, Delaware, Maryland, the District of Columbia and his home state of Illinois.
Mr Obama was performing better in a number of battleground states, including Indiana, than John Kerry did in 2004 and exit polls predicted a victory there for the Democrat.
Voters formed long queues at polling stations across the United States yesterday amid predictions of a record turnout.
Failure to win Pennsylvania would have dealt a serious blow to Mr McCain, who identified the state as the only big prize won by the Democrats in 2004 that he hoped to take yesterday.
Some states reported problems with voting machines and voters sometimes had to wait for hours before casting their ballots, but election officials said most glitches were relatively minor.
Mr McCain, who entered yesterday's election as the underdog, continued campaigning throughout the day, appearing at rallies in the battleground states of Colorado and New Mexico.
Mr Obama held no campaign events but visited campaign workers in Indiana, one of a number of states that have voted Republican in recent elections but which the Democrats were targeting this year.
An Associated Press exit poll found that six in 10 voters said the economy was the most important issue in the election. None of the other top issues - energy, Iraq , terrorism and healthcare - was picked by more than one in 10.
Tens of thousands of people gathered in the centre of Chicago last night for an election night celebration for Mr Obama in Grant Park.
Giant screens were set up to relay the election results and Mr Obama's speech to up to a million people who were expected to attend.
Apart from the presidential election, one-third of US Senate seats and every seat in the House of Representatives were up for election yesterday.
Voters in California were also due to decide on a proposal to remove the right to marry from gay couples.
Democrats appeared set last night to pick up at least one of their targeted Senate seats, with former Virginia governor Mark Warner poised to replace retiring Republican John Warner.
Before the polls opened, an Alaska personnel board cleared Mr McCain's running mate, Sarah Palin, of misconduct in firing a state police chief who refused to dismiss her former brother-in-law from the police force.
Ms Palin, who flew back to her home town of Wasilla to vote, said afterwards that she was hoping and praying for a Republican victory.
"Here in Alaska, where we've cleaned up the corruption and we've taken on some self-dealing and selfinterests, we've been able to really put government back on the side of the people," she said.
"I hope, pray, believe I'll be able to do that as vice-president for everybody in America, helping to transform our national government too."
When an Alaska reporter asked what she would do if Mr McCain lost the election, however, Ms Palin did not hesitate before speculating about an alternative political future.
"You know, if there is a role in national politics, it won't be so much partisan," she said.
"My efforts have always been here in the state of Alaska to get everybody to unite and work together and progress this state. It would certainly be a uniter type of role."