A senior press-gallery journalist, one who frequently accompanies the prime minister on his foreign trips, once informed a gathering at which I was present that when John Howard visited Italy he declined an invitation to view the ceiling of the Sistine Chapel. He preferred to stay in his hotel room, discussing Australian political manoeuvres on the phone. Although this story might be apocryphal, it is not difficult to believe. Beyond family and cricket, Howard is the kind of man whose mind is only seriously absorbed by one thing: politics. With him, the interest in and desire for power is so pure and undiluted that it has the quality of a carnal passion. For him, all roads lead to Canberra, not to Rome.

Since Kevin Rudd was elected leader of the Opposition last December, the opinion polls have invariably found Labor holding a massive two-party-preferred lead over the Coalition of between 10% and 20%. Such a lead by one federal party in the polls, of this size and for this long, has not been witnessed in recent political history. No one knows why it has happened. No one knows whether this kind of polling will last. Only one thing is certain: the prime minister is presently a very worried man. If Howard had retired in the middle of last year, his reputation as one of the most politically successful prime ministers in our history would have been assured. If his government is decisively defeated later this year, the historians will be considerably more parsimonious in their praise.

I once compared the prime minister to an ageing mountain goat. It was not meant unkindly. He has a remarkable capacity to keep his footing even on the most treacherous political slopes. Once or twice in the early days of the Latham Labor leadership, Howard stumbled - over parliamentarians' superannuation, for example - but quickly regained his balance. Only this year has he fallen badly. His reaction has been fascinating to observe.

At first, the prime minister decided to do to Kevin Rudd what he had done to Mark Latham, to diminish reputation by attacking character. The public learnt that Rudd had shown his unfitness to become prime minister because on one occasion in 2005 he had met with the disgraced former West Australian premier Brian Burke; because on another he might have misremembered some details concerning his family's eviction from their home following the death of his father, when Kevin was 11; and because on yet another his wife, who ran a very successful business, had made some inadvertent errors in the payment of some staff. With Latham the tactic worked. With Rudd, interestingly, it did not. Not only did he emerge with his reputation intact; if anything, it was enhanced. Rudd tackled the problem surrounding his wife with delicacy, good humour and tact. When he told the public that Therese Rein was a strong and independent person who made decisions for herself, he was readily believed. The family crisis opened a window onto a contemporary Australian marriage both companionate and attractive. By comparison the obviously successful Howard marriage looked decidedly old-fashioned. Political culture often works in strange ways. It might have been at precisely this moment that the thought about Kevin Rudd as the new generation's John Howard penetrated the national imagination. The story put about last month by some unidentified unit of the Liberal Party's dirt machine - about Rudd's 2003 visit to a New York strip club - accordingly did him no obvious harm.

After the mud came the money. It was obvious that the new industrial-relations laws would be one of the most important issues of the coming election. The government decided to use many millions of taxpayers' dollars to fund a protracted advertising drive - supposedly providing the public with information, but in reality an anti-Labor pre-election campaign. This was not the only instance of the Howard government's lavish use of public money for purposes of this kind.