The Murdoch clan is used to the rest of the media, politicians and the chattering classes trying to decode their political stance and its implications from their public actions.

The early signals were that Rupert Murdoch favoured Hillary Clinton in the US presidential election. But yesterday Murdoch-watchers were digesting the news that Elisabeth Murdoch, Rupert's 39-year-old daughter, who runs a large TV production company, will host a London fundraiser for Clinton's rival, Barack Obama, this month.

Despite the extensive coverage in the UK media, for high-rolling US expats election fever must seem a long way away.

But in the most high-profile example yet of glitzy fundraising bashes for the US presidential hopefuls spreading across the Atlantic, a string of notable US expats with jobs in media, the arts and finance will gather at the Notting Hill home Murdoch shares with her husband, the PR guru Matthew Freud.

So-called "event chairs" at the fundraising evening on April 28 include Hollywood actress Gwyneth Paltrow, Warner Brothers UK chief Josh Berger and Julia Moffett, the director of strategy for the BBC World Service Trust.

Hosts at the bash, VIP tickets for which cost $2,300 (£1,160), include Joanna Shields, the international president of popular social networking site Bebo, which was recently sold to AOL.

Those who have already donated to the campaign are invited to "top up" their donation to the maximum $2,300 allowed under US law.

Rupert Murdoch's News Corp media empire includes the rightwing Fox News, as well as the New York Post, Twentieth Century Fox, BSkyB, the Wall Street Journal and the News International stable of UK newspapers including the Sun and the Times.

His backing is assiduously courted by politicians around the world, with his choices often decided by expediency, and both Labour and the Conservatives are working on securing the backing of his newspapers in time for the next general election. Last year he donated $2,300 to Hillary Clinton's campaign fund, but the New York Post has more recently criticised her campaign and appeared to be siding with Obama.

Prompted by his son James, now head of all News Corp's European and Asian operations, he has also endorsed former vice president Al Gore's environmental campaign.

Elisabeth Murdoch's Shine production company has expanded hugely in the past two years with the purchase of a string of rivals including Kudos, the producer of Spooks and Life on Mars, and Reveille, the US production company behind The Office and Ugly Betty.

She launched the company after leaving a senior executive job at BSkyB in 2000. Contacted by the New York Times, Freud said: "I don't think you can interpret the event as anything other than she is enthusiastic about Obama's campaign."

Both the Clinton and Obama camps have routinely released the names of big name actors, sports personalities and well-known business figures who have backed their campaigns. Clinton's celebrity backers include Jack Nicholson, Elton John, Steven Spielberg and Barbra Streisand, while Obama boasts the likes of Robert de Niro, Scarlett Johansson, Halle Berry and George Clooney.

· This article was amended on Friday April 4 2008. In the article above we originally referred to Joanna Shields as the vice-president of Bebo when she is, in fact, president. This has been corrected.