Despite the high turnout - expected to reach records in several states amid massive campaign efforts to register new voters - problems were minor in Florida, Missouri, Ohio and Virginia, states that Republican John McCain and his Democratic rival Barack Obama have fought over tooth and nail in weeks leading up to Election Day.

In Missouri, a bellwether state which has voted for the presidential winner in every election since 1904 with just one exception, officials were seeing a massive voter response.

'We do have unprecedented turnout,' Ms Laura Egerdal, communications director for Missouri's secretary of state, told AFP, noting that long lines were seen in scores of precincts.

'I think today we are easily going to set a record for the sheer number of voters turning out today,' she said, adding that the state could also surpass the record 78 per cent turnout seen back in 1992.

The state added 342,000 new first-time voters to its rolls in 2008, comprising more than eight per cent of Missouri voters, Ms Egerdal said.

Associated Press exit polls showed that six in 10 voters cited the economy as the most important issue facing the United States. None of four other issues on the list - energy, Iraq, terrorism and health care - was picked by more than one in 10.

The results were based on a preliminary partial sample of nearly 10,000 voters in election day exit polls and telephone interviews over the past week for early voters.

Early morning voting in Kansas City was marred by the misplacement of voting books in some precincts, which delayed poll openings, but Ms Egerdal said the problem was remedied.

Lines were common in Virginia, too.

'It's a phenomenal turnout,' Virginia's secretary of state Jean Jensen told a news briefing, noting that up to 40 per cent of the state's registered voters had cast their ballots by 10.00am (11.00am Singapore time.

'Some (precinct officials) said 50 per cent of Virginians who are eligible to vote have already been to the polls.'

The traditionally red, or Republican, state of Virginia has been under assault by Mr Obama and his campaign, who see wresting it away from Republicans as a key to victory.

Ms Jensen noted there had been several minor problems reported to authorities, including two polling stations opening late due to human error, the malfunction of some optical scanning machines, and allegations of voter suppression and intimidation, including advocacy groups 'being overzealous in their outreach.'

Record turnout was expected in North Carolina - where some polls call the race a virtual tie - despite a steady rain falling across the southeastern state.

'I feel certain we're going to exceed 70 per cent voter turnout,' breaking the state record 69 per cent in 1984, said Mr Johnnie McLean, deputy director of North Carolina's board of elections.

'We have had lots of new voter registrations, record-breaking absentee voting' and huge early voting turnout in the two weeks prior to Election Day, Mr McLean said.

The hard-fought swing state of Ohio was on track for an 80 per cent voter turnout, according to the secretary of state's office.

Mr Jeff Ortega, of Ohio Secretary of State Jennifer Brunner's office, said Ms Brunner's preparations for high numbers of voters helped minimise Election Day problems and keep voter lines down to manageable levels, although some polling stations saw lines of an hour or longer.

'It looks like those efforts bore fruit,' Mr Ortega said.

But election protection website 866ourvote.com did report receiving reports of Ohio voters being 'inexplicably dropped' from lists of registered voters - an issue that had dogged the 2004 election.

A Realclearpolitics.com poll average shows Mr Obama leading Mr McCain in Ohio by 2.5 per cent on Tuesday in Ohio, which is considered a must win for Mr McCain.

The last person to win the presidency without winning Ohio was Mr John F Kennedy in 1960. In 2004, Mr Bush won Ohio by only 118,000 individual votes.

In Florida, scene of an Election Day debacle four years ago that led to a controversial recount, election officials reported no major incidents or problems in Miami Dade and Broward counties.

But there were news reports of voting machines breaking down and needing replacement in two Sarasota precincts. -- AFP, AP

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