ON A chilly day in central Melbourne, Cath Bowtell is courting Labor votes. Adam Bandt, a rival Green, campaigns nearby. Both are drawing abuse from a jobless man selling a community newspaper who resents politicians cluttering his patch. But the candidates stand their ground: Melbourne could prove crucial in deciding Australia's tightly fought general election on August 21st.

The ruling Labor Party has held this constituency for 106 years. The incumbent is Lindsay Tanner, the finance minister, who commands a strong following among the educated young professionals who have changed its old working class character. But Mr Tanner announced that he was quitting on the day in June that Julia Gillard unseated Kevin Rudd as Labor leader and prime minister. It was the first act in a soap opera that has since bedevilled Labor's campaign against the conservative Liberal-National opposition.

Polls since then have shown support in this progressive corner drifting to the Greens. Voters are uneasy that Labor dropped plans for an emissions-trading scheme to tackle climate change, and many dislike Ms Gillard's populist approach on asylum-seekers (though it is softer than that of the opposition). As a result, the Greens hope to capture Melbourne as their first-ever seat in the country's lower house. Having enjoyed a majority of 16, some glum Labor folk now talk of a hung parliament: two safe inner-Sydney seats are also under a Green siege. Mr Bandt says that “People seem to think the Labor Party has become more like the Liberal Party.”

For Ms Gillard, battling to avoid the humiliation of a Labor defeat after barely a single term, the Melbourne bind stretches over the country. A poll on August 9th gave Labor a four-point lead over the coalition, once second-preference votes were counted. The real story, though, lies in first votes. Labor's have dropped by almost five points to 38% since the last election in 2007; the coalition's tally is roughly unchanged at 42%. Green support has risen by almost four points to 12%, mostly at the expense of Labor. To stay in power, Ms Gillard will probably have to rely on a preference-vote deal with the Greens.

This was hardly the script Labor's chiefs had in mind when they launched the coup to install Ms Gillard. At 48, her popularity and gift for plain speaking were meant to rescue the government from Mr Rudd's falling poll ratings. The dispatched leader, though, became a bigger media draw than his successor. In pictures of the pair meeting again on August 7th in Brisbane, Mr Rudd's home city, they looked more like two warring relatives than colleagues out to win an election. By the campaign's penultimate week, however, Ms Gillard had started to cut through. She went to resource-rich Western Australia in a bid to calm lingering protests over a new mining-profits tax. And after fielding questions smartly from a national television audience, bookmakers shortened the odds on her being elected Australia's first woman prime minister in her own right.

If Ms Gillard is still straining to convince voters, Tony Abbott, the opposition leader, is faring little better. A competitive, combative figure in the right-wing mould of John Howard, a former long-serving Liberal prime minister, he was hardly considered a serious contender for his party's leadership. He snatched it by just one vote eight months ago. His formal campaign launch on August 9th in Brisbane, before Mr Howard and other Liberal diehards, was big on attack, slight on policy.

If he wins, Mr Abbott promises to ring the leader of the Pacific island nation of Nauru and reinstate a discredited Howard-era policy of dumping boat people there. Ms Gillard, meanwhile, is trying to embarrass Mr Abbott over a plan to pay for a parental-leave scheme by raising company taxes, saying it will only put up costs. Business leaders have attacked his promise to abolish Labor's A$43 billion ($39 billion) fibre-optic broadband project and replace it with a cheaper, lesser one.

Yet Labor has squandered the electoral advantage that might have been its due from keeping Australia out of recession in the global downturn. Ross Garnaut, an economist and former adviser to the Rudd government, argues that income growth from the China-led resources boom will peak this year. He recently attacked both main parties in the election for failing to tackle declining productivity. And neither leader has offered any vision for Australia's relations with its region, especially China, its biggest trading partner.

Selling the economy strongly still remains Ms Gillard's best hope. She will be helped, too, if she can stop her party's infighting and if Mr Abbott manages one of his periodic verbal gaffes. Yet this uncertain mix hints at how this election, more than most, has entertained and dismayed Australians in near equal measure.