BATTLEGROUND: (Above) John McCain's campaign released a TV commercial comparing Obama to popstars

John McCain's presidential campaign yesterday released a television ad comparing Barack Obama to Britney Spears and Paris Hilton, suggesting the Democratic contender is little more than a vapid but widely recognised media concoction.

Obama's campaign quickly responded with a commercial of its own, dismissing McCain's complaints as 'baloney' and 'baseless'.

McCain's ad, titled 'Celeb' and set to air in 11 battleground states, intercuts images of Obama on his trip to Europe last week with video of pop stars Spears and Hilton - both better known for their childish off-screen antics.

"He's the biggest celebrity in the world, but is he ready to lead?" the voiceover asks, noting the Illinois senator's opposition to offshore oil drilling and suggesting he would raise taxes if elected.

It was the latest effort by the GOP hopeful to cast Obama as a lightweight with little experience in leadership or governing.

Campaigning in Missouri, Obama said, " McCain doesn't seem to have anything positive to say about me, does he? You need to ask John McCain what he's for, not just what he's against."

The Obama campaign ad, released hours after McCain's, shows images of the Arizona senator with President Bush and accuses McCain of practicing "the politics of the past."