I am sure they thought they were being very clever. I can almost see them chortling in the video editing suite. But they have made a ghastly error.

Intercutting pictures of Barack Obama with Britney Spears and Paris Hilton is a stunt you pull when you confuse your own view of your opponent with everyone else's view.

If Barack Obama was regarded by the public as being like Britney and Paris he wouldn't be the figure he is. In other words, if the advert accorded with the voter's view of Mr Obama you would hardly need to make it.

The McCain camp, I am sure, hopes the ad will help shape the view of Mr Obama. But they are ignoring a golden rule of politics - your attack ads also shape views of you. Whether or not the film makes Mr Obama look smaller, it certainly makes John McCain look smaller.

The advert features one other error. It shows a massive crowd chanting “O-ba-ma”. Why would you feature this in a McCain campaign film? You hardly need to be the most attentive student of the science of persuasion to realise that the endorsement of large enthusiastic crowds is one of the most potent tools of influence. This image just screams “Vote Obama”. An odd choice of footage, to say the least.

xxx

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