The years 1904, 1939, 1941 and 1945 rank as highly unusual years in Australia’s political history, with the very real possibility that they could soon be joined by 2007.

Each of these landmark years in the last century saw Australia with three prime ministers within each 12 month period, and it could happen again.

In the first instance listed above, Alfred Deakin’s first government made way for a short-lived Labor government, Australia’s first, headed by Chris Watson, which fell and gave way to George Reid’s coalition of Free Traders and Protectionists. In 1939 Joe Lyons died, the baton passing briefly to Country Party leader Earle Page before the election of Robert Menzies, and when Menzies was driven from the leadership by his own party, Arthur Fadden held the reins momentarily until two Independents supported the ALP and John Curtin became prime minister. When Curtin died in 1945, Frank Forde was in charge for eight days until caucus elected Ben Chifley.

So what do any of these sets of circumstances have in common with 2007 where we have a prime minister in rude health and commanding large majorities in both party and parliament? On the surface there is nothing in common, but here is a possible scenario.

The opinion polls continue in free fall for the Liberals for a raft of reasons, not least because a rightly sceptical electorate is openly laughing at John Howard’s new found concern for David Hicks and sudden interest in global warming after years of scoffing and rejection of Kyoto.

Come mid-year and the situation is even worse, with already jittery backbenchers, especially those in marginal seats, now openly rebellious.

John Howard, who has made no secret of his desire to emulate Menzies (in his second incarnation as prime minister, not the first) to go at a time of his own choosing decides, “for the good of the party”, to step down. (Cunningly, with an eye to history, he also avoids being branded as the leader who overstayed, or as the Liberal who lost an election, like Billy McMahon and Malcolm Fraser, because the Libs are a mercilessly unforgiving lot).

So, does Peter Costello get his wish and move into the Lodge?

No. The party, now desperate, takes the view that everything that made Howard so unpopular also applies to Costello (the man who sold out Qantas) who has been there in lockstep with Howard since the win in 1996.

And history teaches just how desperate Liberals facing defeat can be: after all, they elevated the hapless and hopeless McMahon to the leadership in 1971 after John Gorton’s prime ministership imploded and the air was already rank with the stench of defeat.

At least they turn to someone credible, a man who already looks and sounds like a prime minister, yet remains generally untainted with whatever ordure derives from 11 years in government, and come July Malcolm Turnbull is prime minister.

Like Kevin Rudd, he presents a fresh new face, articulates a vision of sorts and inspires confidence. But the problem is that six months out from the election, the voters have already made up their minds, and Turnbull’s freshness is wasted on the desert air.

The election is held as late in November as can be arranged, and Labor wins. Kevin Rudd becomes, early in December, the third prime minister of the year.

Implausible? Not at all. In fact, some essential groundwork has already been laid by John Howard himself, a man who always chooses his words very carefully. Why has he not stepped down in favour of his Treasurer? Because the party has wanted him to stay on, and as long as that is the case, he stays on.

Should the party come to another view – especially when staring down the barrel of defeat – he, the humble servant that he is, would simply reiterate the same view, claiming as always a virtuous consistency.

Not only would someone else be leading the doomed charge; it would also resolve the little problem in Howard’s own seat of Bennelong, which, of course, he would not recontest, and thereby avoid the humiliation of becoming only the second prime minister, after Stanley Bruce in 1929, to lose his seat.

Stranger things have happened.