The Huffington Post, bastion of liberalism, is sold for $315m

(AP)

Arianna Huffington was in her element last week, toasting the makers of The King's Speech at a cocktail party at her Los Angeles home, hobnobbing with the conjured contents of her Rolodex and flaunting her current status as new media visionary.

Stuttering old George VI would, she said, have had fewer communication problems today, since he could simply take to Twitter. Or, for that matter, write a rousing piece for her website.

As Colin Firth and Helena Bonham-Carter mingled with genuine British aristocracy, including Lady Victoria Hervey and Earl Spencer, and with Hollywood royalty, including Oliver Stone, Huffington chitchatted and posed for photos with all of them.

She gave no indication that she was on the verge of sealing one of the biggest media tie-ups in recent times in a deal that would cement her status as one of the internet's most significant opinion-formers for years to come.

Created just six years ago, huffingtonpost.com has become an online focal point for American liberals, serving a daily diet of left-leaning political news, links to the best of the rest of the web, and provocative commentary from a roster of columnists.

And in the small hours of yesterday morning, Huffington announced she had sold it. The internet giant AOL is paying $315m (£199m), mainly in cash, to Huffington and her co-investors, and she herself will now take charge of a much larger, merged media empire, under the title of editor-in-chief at AOL's content division.

The creation of the Huffington Post in 2005 displayed the cocktail party host at her very best. As a liberal mirror to the Drudge Report, which aggregated news from around the web for a conservative audience, the website might never have taken off. But Huffington called round several hundred of her rich and famous friends and charmed them into blogging for her. Even today, lured by the anti-establishment aura of the website, not to mention the prospect of reaching its 25 million regular readers, big name commentators are willing to write for little money or for free.

That roster of occasional bloggers has included many of the biggest figures in the Democratic party, from John Kerry to Hillary Clinton, and Hollywood stars of a political or an environmentalist bent, from Jamie Lee Curtis to Mia Farrow, as well as all the usual suspects from the liberal commentariat. There are a few Republicans, too, not least the former Congressman-turned-gay rights activist, Michael Huffington, with whom Huffington has remained close since their divorce in 1997. He was also in attendance at last week's party, with his current boyfriend.

"I want this to be my last act," Huffington said yesterday during the obligatory round of public appearances alongside her new boss, AOL chief executive Tim Armstrong. Taking charge of the rest of AOL's editorial content, which includes specialist websites such as TechCrunch and its local news network Patch, could not be more exciting, she said, "like stepping off a fast-moving train and on to a supersonic jet... I've done a lot of different things in my life, but there is nothing else I want to do".

A lot of different things, she said. She is not kidding about that. To those whose first encounter with Huffington has been in the past decade, it still comes as a shock to find she was a searing right-wing commentator in her earlier days. Born Arianna Stassinopoulous in 1950, the daughter of an Athens journalist, she moved to the UK at age 16 and became only the third female student to chair the Cambridge University debating society, the Cambridge Union.

Her eclectic post-university career included journalism and acting and appearances on radio shows such as Any Questions and TV panel games. She lived with the British columnist and broadcaster Bernard Levin, more than 20 years her senior, for many years, before leaving him for a new start in American media and political circles.

The prominent role she played in her husband's near-miss campaign for a Senate seat in California put her on the map in Republican politics, and her first online venture was Resignation .com, a website for voters who wanted to impeach Bill Clinton.

But Huffington was already on her extraordinary journey towards liberalism, a journey that was accelerated by what she saw as the horrors of the George Bush presidency and her growing environmentalism. In 2003, with funds from her multi-million dollar divorce settlement, she mounted an independent bid for the California governorship. It was, she said, the "hybrid versus the Hummer", as she traded insults with front-runner Arnold Schwarzenegger over his green credentials.

Her campaign never took flight, but her media profile only rose, gathering followers for the particular brand of liberalism espoused through Ariannaonline, a precursor website to the Huffington Post. Aiding her indefatigable self-promotion has been the fact she maintains a distinctly Greek accent, making her parody-able. She has even parodied herself, with cameos on comedy programmes such as Family Guy.

Along the way, she has alighted on what looks like one of the few winning formulas for internet journalism: a media brand spun around a powerful individual personality.

The only question still hanging today is whether the business side really will work out. Huffington Post was modestly profitable last year, and is expected to bring in revenues of $60m or so in 2011. But AOL is paying a hefty price to get its hands on an internet brand with real clout. Huffington and her business partner Ken Lerer put about $2m of their own money into the venture back in 2005, and raised $35m or so more for other investors. They have made a healthy return. If AOL manages the same, it will be defying the conventional wisdom. Yesterday, just a few hours after its purchase was announced, its shares were down 4 per cent. It was an inauspicious start.