WASHINGTON DC: This year's US presidential election is likely to set a record for the number of advertising dollars spent on television as each of the White House hopefuls tries to persuade voters he is the right man for the job.

Total TV adspend is expected to reach £800 million (€506m £402m), a significant increase on the previous record of $500m, set in 2004 by incumbent George W Bush and challenger, John Kerry.

The 2008 battle between Democrat Barack Obama and Republican John McCain is likely to see increased adspend on local and network TV of between 2% and 3%, and a 6% rise on cable TV, according to media buying group ZenithOptimedia.

The CBS TV network pocketed $30m in political ads during the first quarter of the year as Obama battled with Hillary Clinton for his party's nomination.

The would-be leader of the free world has already raised $286m for his campaign, with many millions more dollars expected to pour into the warchest before November's final skirmish.

Obama's camp has already snapped-up airtime in solid Republican states such as Alaska, Montana and Indiana, as he tries to force his opponent to defend territories he would otherwise take for granted.

In addition, Obama could advertise nationally during coverage of the Beijing Olympic Games or the World Series baseball extravaganza, and target select audiences on cable channels such as MTV.

McCain's campaign will be limited to $85m of public money during the last two months of the battle because he did not opt out of the public campaign-finance system. He will have to pick his ad spots with care to make best use of the available cash.

Data sourced from Washington Post Online; additional information by WARC staff