The new face of US politics, one that the Founding Fathers would never have contemplated, is flickering over computer screens across America.

By lunchtime yesterday, 894,279 people had viewed a YouTube video of a model prancing around New York in various stages of undress while lip-synching the words of a song declaring that she has a crush on Democratic presidential candidate Barack Obama.

“Baby, I cannot wait/ til 2008/ Baby, you’re the best candidate,” she says, pushing out and then hugging her breasts which are covered by a tight T-shirts. “You’re into border security/ let’s break this border between you and me/ universal health care reform/ mmm – it makes me warm.”

Mr Obama’s campaign, which had nothing to do with this $2,000 home made video, has issued a po-faced “no comment” about it. He has previously chastised reporters for writing about how good his toned body looked in a swimming costume – photographs which unsurprisingly reappeared in the video where the model, Amber Lee Ettinger, draped herself over his bare torso.

This year YouTube and CNN will team up to host live presidential debates for the first time in which video-makers are being asked to create 30-second snippets asking candidates questions on issues they believe to be important.

Mr Obama, however, appears to be caught in a dilemma over how to capitalise on the energy he sparks among the YouTube generation. Although it offers him access to an untapped supply of money and activists, he appears to be deeply uneasy about the unfiltered – sometimes frivolous – nature of online politics.

He deliberately keeps his distance from the “net-roots” of liberal Democrats in the blogosphere. And earlier this year his campaign was widely criticised for seizing control over a MySpace group where an enthusiastic supporter, Joe Anthony, had amassed a list of 160,000 friends for Mr Obama.

His optimistic political brand, in which he promises a new kind of positive politics and a campaign owned by his supporters, is also being undercut by disclosures about negative tactics employed by aides.

Last week, he was embarrassed by the leaking of a classified memo distributed to sympathetic members of the press which highlighted Hillary Clinton’s links to Indian donors and described her as the Democratic senator for the Punjab.

Mrs Clinton, who is usually seen as more brittle and controlling than Mr Obama, has earned some limited respect among younger voters for an online poll on what should be her campaign song. Her website has even included her featuring videos of voters denouncing the idea as crazy and demeaning.

The “Obamagirl”, intended in part as a response to Mrs Clinton’s efforts, is meanwhile offering up for auction her T-shirts, bikini and the tiny red “booty-shorts” emblazoned on the back with the letters O-B-A-M-A.

Although she lip-synchs to the words “you tell the truth unlike the right/ you can Barack me tonight”, Ms Ettinger has not ruled out making videos for other candidates.

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