Scott Morrison is starting to show that he is feeling the pressure of a ramp up in scrutiny.

He is getting more combative, both in the pressers and in the Parliament. People want answers.

His past brush-offs are wearing thin.

His electoral strategy has been to rely on his strong personal popularity in the polls, on the recent budget to neutralise key issues and constituencies and sustain the run of good economic numbers through to the election, and on incumbency.

Although Morrison has been able to maintain his personal popularity in the polls, this hasn't been enough to regain the lead in the two-party vote.

It has surprised many that he has been able to sustain this popularity through the COVID-19 pandemic, when it was the states - rather than him - that did the heavy lifting in containing the virus.

Moreover, he was able to duck clear national responsibility for quarantine and aged care, with the states carrying the blame for the failures in both.

The explanation seems to be that overall Australia has done pretty well relative to most other countries in managing the virus and the economy, and nobody really wants to be seen to rock the boat.

There is no doubt that the government has enjoyed a run of good economic data, so far, especially the growth and unemployment numbers.

Of course, it should have against the early dire predictions, given that the numbers have been recovering with the help of government spending about 15 per cent of GDP, and being driven by significant pent-up demand.

Although we seem to have recovered the pre-COVID level of GDP, there is still and "output gap" of about 10 per cent of GDP, relative to what would have been achieved without the pandemic.

While the government put a strong spin on the "good April employment news", it really wasn't.

Total employment fell by some 30,000, and the only way the unemployment rate fell was that some 60,000-plus gave up looking for work.

The government went out of its way to sell this as indicating little effect from the ending of JobKeeper at the end of March.

It is still early days, and it is not unreasonable to expect employers may take some time to make final employment decisions.

It will also take time for the full impact of the reinstatement of solvency requirements, and the ending of rent and debt payments moratoria, to flow through.

There is no doubt that incumbency has been a real advantage in the recent state elections in Queensland, Western Australia and Tasmania, and Morrison has a reasonable expectation that the same feelings will carry through to his re-election.

The main issue in each case seems to have been personal safety and security during the pandemic - the premiers standing up for their residents.

Morrison is obviously hoping that this sentiment carries through to him, even though he is now widely seen to have made a mess of the vaccine roll-out, with a growing hesitancy to get the jab.

The government's boast late last year that it had tied up some 160 million doses has been seen to have been a ridiculous exaggeration.

It is now grappling with serious limits on supply, making it hesitant to launch a full-scale marketing campaign to encourage vaccination, as concerns mount in the community about certain vaccines, possible blood clots and other side effects.

Beyond this, Morrison has so far been able to duck accountability for the declining integrity of his government, his failure to act on climate change, and his failure to put in place a strategy to sustain, not just secure a longer-term economic recovery.

It is indeed most surprising that issues such as sports and other rorts, sexual misconduct in the Parliament, ministerial failures and missteps and his failure to deliver the promised national Anti-Corruption and Integrity Commission are yet to dent his poll standing.

On climate, Morrison has simply ignored the science and market realities, confirming our position as a global laggard, clinging to old fossil fuel technology responses - favouring coal, gas and dirty petrol.

Morrison's gamble is that he can continue to hold it all together until the election.

This will be increasingly difficult to do, suggesting he will buckle and go to the polls sometime between September and November.

Morrison cannot control the virus' behaviour as he assumes, and he will certainly want to go to an election before international borders are reopened.

John Hewson is a professor at the Crawford School of Public Policy, ANU, and a former Liberal opposition leader.