WASHINGTON, Oct 21: Next month's US presidential election is set to smash all spending records, according to an independent study released on Thursday, which estimates that more than a billion dollars will be spent on the race for the White House by election day.

The study by the independent Center for Responsive Politics found that combined spending on White House and congressional races will reach a record 3.9 billion dollars - almost a third more than the last election.

"Overall, if we look at what the federal elections are expected to cost in 2004, we're looking at about a 30 per cent increase over 2000," Larry Noble, the centre's director, said.

Mr Noble said the centre's figures are based on conservative estimates and that total campaign spending is likely even higher, since the study focused only on the top spenders in presidential and congressional elections.

"The cost of campaigning continues to increase, the cost of our elections continue to increase," said Mr Noble.

The centre's research found that spending increases were partly a result of advent of independent "527" groups that have overshadowed the 2004 campaign.

The 527s - political advocacy groups which enjoy tax benefits because of their non-profit status - named for the legal code that defines them.

The groups are allowed to fund partisan advertisements as they are independent of a candidate's political campaign.

"527 organizations are having an impact on how much is being spent in the election," said Noble.

"We're expecting them to spend about 386 million," on federal races he said - or about one tenth of all 2004 campaign spending. The centre estimated that 527s will spend about 187 million dollars on the presidential race alone.

527 groups have been responsible for some of the most controversial and influential ads during the presidential election, and there have been increasing calls - as well as proposed congressional legislation - to more strictly regulate them.-AFP