The convention that kicks off on Monday in Denver and will crown Barack Obama as the Democratic Party's presidential candidate will be a transforming moment in politics. But it could be just as big a spectacle in the annals of American media and technology, the moment when the new kids on the block eclipse - or at least grab equal footing - with the so-called establishment.

Call it the Obamedia Frenzy. In Denver, the hordes of media from newspaper, magazine and cable and broadcast news outlets will be competing for stories with scores of bloggers and so-called citizen journalists kitted out by digital juggernauts Google, MySpace and YouTube.

There will also be writers from two influential online news sites that did not exist four years ago, The Huffington Post and Politico - not to mention unconventional outlets like The Daily Show with Jon Stewart, a nightly comedy programme that has become one of the nation's most trusted news sources.

While allcomers have occupied their own neat space in the media maw, the Democratic National Convention will be the first time they all have the potential to trip over each other in close physical proximity: about 15,000 journalists of all stripes are expected to be there from around the world.

At a time when many so-called mainstream news organisations in the US are grappling with shrinking newsrooms, shuttered news bureaus and identity crises, the disruptors and interlopers will be in plain view. Google, which owns the website blogger.com as well as YouTube, has set up an 8,000 sq ft facility called The Big Tent next to the arena where most of the convention is being held.

Inside, for only $100, journalists and bloggers get free food, beer and wi-fi for four days, and has a kiosk set up for uploading videos to YouTube. Sounds neat? Sure. And let us not forget that nearly half of all video watched online in the US is seen via Google, and its market capitalisation, at $152billion, is greater than CBS, Time Warner, Walt Disney, The New York Times, The Washington Post, and Viacom combined.

MySpace, which was a year-old start-up at the time of the previous convention, claims that about one in four Americans are registered users. It plans a series of events surrounding the convention, some of which will be held at MySpace Cafés where people can go online to update their sites.

Having recently built up a political “channel” on MySpace called Impact, the social network also held a contest with MSNBC to select a “citizen journalist” elected to cover the event and post to their sites. In his video entry, the winner, a 23-year-old from Michigan, joked: “I don't know, maybe I'll interview the janitor at the convention.”

Kidding aside, like MTV before it, MySpace (which, like this newspaper, is owned by News Corp) is determined to show that it is a potent societal as well as cultural force - Obama has almost 454,000 “friends” on MySpace, only 30,000 or so fewer than the band Coldplay, and a whole lot more than John McCain's nearly 64,000.

Lee Brenner, MySpace's 31-year-old producer of political programming and a former producer at CNN, said that the role of social networks and blogs during the election race is different from more traditional outlets because it is about getting users to participate. “We're trying to democratise democracy,” he told me. “We're not trying to just give information.”

The convention will also be a defining moment of sorts for Huffington Post and Politico, which have found niches in a relatively short time by using very different approaches. John Harris, Politico's editor-in-chief, said that most of the service's roughly 40 journalists would be deployed at the convention.

Politico launched at the beginning of 2007 after luring Harris and Jim Vandehei, his colleague, away from long careers covering politics at The Washington Post, with the promise of coverage that was deeper and faster than anything in the mainstream. In terms of how Politico will stand out from the pack in Denver, Harris says, “Our readers are like us and they have a political screw loose. Quite un-selfconsciously, we write for junkies.” According to Nielsen, Politico's website has more visitors than some of the country's biggest newspapers, including The Dallas Morning News and The Philadelphia Inquirer.

The Huffington Post has a rather different model, presenting a daily stew of unpaid blogs, links to breaking news stories and original reporting by its own small staff of journalists - highlighted by Arianna Huffington, the founder and editor-and-chief. She might be something of the belle of the ball among media attendees, given her three-year-old site's conception as a kind of liberal antidote to the powerful and conservative-leaning Drudge Report.

According to Nielsen, Huffington Post's web audience in July ranked ahead of all but 11 newspaper websites. Huffington, Greek-born, Cambridge-educated, is an unlikely queen of the web at 57. She will be making the rounds doing political panels and signing copies of her latest book, Why Right is Wrong. But she will also be using the venue to promote the softer side of her burgeoning online venture, such as her site's new “living” section.

At The Huffington Post Oasis, right next to Google's Big Tent, attendees are invited to “unplug and recharge” and treat themselves to yoga sessions, smoothies, massages and mini-facials. “All our team is going to be there,” she says. “But part of what we wanted to do is present the Huffington Post as being more than politics.”

That said, the site's founder is looking forward to what happens on the convention floor itself, in particular who Obama will choose as his vice-presidential running mate. And she notes that few of the attendees - old or new - have been more web-savvy than Obama himself.

An e-mail from the candidate's campaign manager to supporters points out that they can sign up to be “the first to know” when he selects his vice-president. “You will receive an e-mail the moment Barack makes his decision,” it says. No need to be in Denver at all.

- Richard Siklos is an editor-at-large at Fortune Magazine

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