Ex-lovers play out political soap opera on Bondi Beach

It is the "jewel in the crown" of John Howard's Liberal Party: Australia's most affluent electorate, comprising Bondi Beach and a swathe of Sydney harbourside suburbs with multi-million dollar views.

But thanks to boundary changes, Wentworth – held by Mr Howard's Environment minister, Malcolm Turnbull – now includes Sydney's infamous red-light district, Kings Cross, as well as low-income areas and the city's principal gay neighbourhood. A bastion of conservatism for the past century, it is considered one of the Liberals' most vulnerable seats, in danger of being lost in Australia's elections a fortnight today.

That should be good news for Mr Turnbull's Labour opponent, George Newhouse, a former mayor of Bondi and human rights lawyer who took on the government in two notorious cases of women illegally detained by immigration.

However, while Mr Newhouse needs a swing of only 2.5 per cent to wrest the seat from the Liberals, he faces a daily irritation in the shape of his former girlfriend, Danielle Ecuyer. A glamorous former merchant banker, Ms Ecuyer decided to stand as an independent in Wentworth just after the couple split up – to upset Mr Newhouse's campaign, some observers believe.

While Ms Ecuyer, now an environmental activist, denies being engaged in a vendetta, she appears to be enjoying upstaging her ex- partner. Yesterday, for the benefit of the media, she was carried across Bondi's golden sands on a surfboard by two bare-chested "hunks".

For Mr Turnbull – a former lawyer who successfully defended the former MI5 agent Peter Wright in 1986 in his battle to prevent the British government banning his memoir Spycatcher – it is not just Wentworth's Labour and Green voters who present a threat.

His approval of a controversial pulp mill in a scenic Tasmanian valley could see well-heeled but environmentally conscious constituents turn against him. Some traditional Liberal voters are also unimpressed by the government's refusal to sign the Kyoto protocol on cutting greenhouse gas emissions.

The pulp mill has also cropped up in the Newhouse-Ecuyer soap opera. At a debate on climate change this week, Mr Newhouse was drawn to speak after Ms Ecuyer. That meant they were supposed to sit next to each other, but he ostentatiously moved to the end of the table.

With the opinion polls pointing to a defeat for Mr Howard's government after 11 years, the Liberals need to keep seats like Wentworth. So Mr Turnbull would probably not relish the sight of a full-page advertisement by Ms Ecuyer in the local paper, declaring "You can pulp him" next to his photograph.

While his own environment policy is causing Mr Turnbull grief locally, so is the government's stance on gay issues. Mr Newhouse has promised that Labour, if elected nationally, will reduce 58 laws that discriminate against gay people.

Mr Turnbull – tipped as a future prime minister – is so desperate to keep his seat that he reportedly tried to persuade the cabinet to sign up to Kyoto recently.

His wife Lucy, a former lord mayor of Sydney, has tried to boost his campaign, distributing a letter saying her husband, the country's wealthiest politician, was misunderstood. "Malcolm did not grow up in a privileged environment as many people believe," she wrote.