Government’s tend to do poorly in by-elections, as by-elections are often seen as an effective way to register a “protest” vote against the government of the day – at the very least, to send them a message. There have been 147 by-elections since 1901 and the average two-party preferred swing against the government has been 4 per cent.

Although recent polling is hard to read, the government has a chance in both Longman in Queensland and Braddon in Tasmania. Both are seats presently held by the ALP, where the candidates were ruled “ineligible” due to their dual citizenship.

Opposition Leader Bill Shorten is particularly exposed over the by-elections, as he had repeatedly given a “rolled gold guarantee” that none of his team would be found to be dual citizens. The High Court disagreed.

Obviously, the Turnbull government is desperate for some “good” electoral news having lost (that is Abbott and Turnbull together) over 65 consecutive NewsPolls to the ALP, although Turnbull has consistently led Shorten as preferred Prime Minister, with the margin widening significantly recently.

So, the question is, would Malcolm be tempted to call an early election if he were to win Longman and/or Braddon?

The reality is that he doesn’t have much flexibility as to timing. If he wishes to hold a full house/half Senate election, as would be normal, he needs to go before May 18 next year. The next Victorian election is due on November 24, and the next NSW election is scheduled for March 23 next year. He needs a campaign of a minimum of 33 days, and he would presumably wish to avoid any overlap with these two state elections.

His timing will be further complicated by probably wanting to avoid school holidays, Christmas, perhaps January holidays, cricket and tennis, and so on. Of course, there are also the AFL/NRL grand finals on September 29-30, and the preliminary finals in the weeks leading up to those dates.

While, clearly, Malcolm may not worry about being constrained by such events and considerations, his “least painful” opportunity would be to go in the first half of September. Parliament is not scheduled to resume until August 13, so he could call the election just before then, for say September 15. Of course, this is pure, but somewhat logical, speculation. But, according to the old adage, you don’t call and election until you think you can win.

Undoubtedly, Malcolm and his government would be buoyed by a win next Saturday, which would also raise questions about Shorten’s hold on the leadership, and rekindle speculation about Albanese vs Shorten. Malcolm could wait a week or so to see how all that unfolds, exploiting every opportunity to destabilize the Opposition.

However, there is a view that Shorten is Malcolm’s “best asset”, so he may not want to see a change of leadership, just sustained speculation and instability.

Another, and I suggest very important consideration, is the state of our economy, against the background of one of the most risky and unpredictable global environments, both the prospects for the global economy, and given the mounting geo-political tensions.

The risks of another global financial crisis are building daily, compounded by the possibility of a trade war, and other financial retaliations to Trump’s tariffs, with the US Federal Reserve still committed to several more increases in US interest rates.

The global debt overhang is unsustainable, with bubbles in stock, bond, property, and currency markets vulnerable to a “correction”. All again compounded by Trump’s volatility and domestic vulnerability – so much now depends on how others respond – and, of course, the US Congress and the Mueller probe.

In these terms, the longer Malcolm leaves it to call an election, the greater the risks he runs that these global tensions will unfold to our national disadvantage, and to the detriment of our economic performance and prospects. But then, we should recognise that Malcolm just loves being Prime Minister. As such he may just be tempted to hang in there as long as possible?