Sen. Barack Obama has swept aside a characterisation of him as a vacuous celebrity in a new commercial broadcast by Sen John McCain's campaign team.

The adverts, likening Obama to celebrities Paris Hilton and Britney Spears, have kicked off a new negative phase of the campaign from the McCain camp. The adverts hint that, while the young Illinois senator has the undoubted capacity and charisma to draw huge crowds (the commercials showed shots of the recent huge Obama rally in Berlin), like the pop icons, he does not have the capacity to lead.

"He's the biggest celebrity in the world, but is he ready to lead?" the ad asks. [source]

The McCain campaign team has stepped up its anti-Obama rhetoric in recent days in tactics reminiscent of legendary (infamous?) political operative Karl Rove who used attack ads to great effect to win his boss, George W. Bush two terms in the White House.

McCain himself was the target of an untrue whisper campaign during the Republican primaries in 2000, alleged to have been started by Rove, which saw the senator subjected to rumours that he had fathered a baby by a black woman. McCain and his wife had adopted a Bangladeshi child, however the rumours played their part in eroding McCain's lead over Bush.