It is hard to remember when the Coalition, under either Malcolm Turnbull or Scott Morrison, last led in an opinion poll.
Labor’s frontbench has been stable for years, while the Government has been plagued by constant chaos and infighting.
And the Prime Minister already leads a minority government, meaning any swing against him on May 18 could be fatal.
But in recent days, cracks have started to appear in Mr Shorten’s apparent inevitability.
The Opposition Leader’s incessant focus on health policy, bolstered by a daily stream of cancer funding announcements, has gradually been eroded by his underwhelming responses to curly questions from reporters.
At a press conference in Adelaide yesterday, Mr Shorten was repeatedly put on the back foot as he refused to properly answer questions about the effect his party’s renewable energy target would have on the economy.
“You have focused almost exclusively, since your Budget reply speech, on health. When can voters expect to learn more about Labor’s emissions reduction target, how you’re going to get there, and the cost to the economy?” Channel 10 journalist Jonathan Lea asked him.
“Well first of all, I haven’t spoken exclusively about health,” Mr Shorten began.
“To be fair, some of your staffers said the same in private conversations, you’ve focused pretty exclusively on it,” Lea replied.
“I don’t know what private conversations you have with people or what you want to reveal,” Mr Shorten shot back.
“I just said, four minutes ago, that Mr Morrison loves to boast about his strong economy. I’m pretty sure we were all here when I said that.”
He went on to claim Mr Morrison’s so-called strong economy was built on “low wages” and “the reduction in real spending on services”.
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That answer did not satisfy the reporter.
“You’re not answering the question Mr Shorten,” Lea said repeatedly.
“Oh OK,” Mr Shorten said with a chuckle. “I’m going to give someone else a go.”
But Lea pressed on.
“When can people know, Mr Shorten, the cost to the economy?” he said. “You didn’t answer the question.”
“Do you know what, Jon? I’m going to go to the next person,” the Labor leader said.
“No, you should answer the question. That’s why we’re here, to ask questions. You’re not answering the question. Why can’t you answer the question Mr Shorten?” Lea said.
“Because I’m going to give your colleagues half a go,” Mr Shorten said, before finally managing to move on to the next questioner.
It was obviously a subject Mr Shorten did not want to discuss. Even today, when he came back better prepared, his claim that Australia’s GDP would grow by 23 per cent over a decade with Labor’s target begged for more scrutiny.
How did Labor come up with that figure? Would GDP growth be higher or lower without the target? Absent that crucial context, it was close to a meaningless statistic.
Mr Shorten also committed his first real gaffe of the campaign yesterday when he claimed Labor had “no plans to increase taxes on superannuation”.
He seemed to be ignoring, or to have forgotten, a suite of policies Labor had already announced, which the Government estimates will add $34 billion in revenue to the budget over the next decade.
Today he claimed to have issued the false claim after misunderstanding a question.
“I thought I was being asked do we have any unannounced changes to superannuation, and we’ve already made the announcements of the changes we’re going to make,” Mr Shorten said.
He disputed the characterisation of Labor’s policies as “tax increases”, but Shadow Treasurer Chris Bowen eventually admitted the measures would raise $30 billion in revenue.
It is becoming clear that whenever Mr Shorten is drawn away from his preferred topics, his campaign is on shakier ground.
Meanwhile, Mr Morrison has been enjoying a relatively smooth ride.
He suffered a small gaffe of his own on the weekend when he greeted a Korean-Australian woman with the Mandarin phrase for hello, “ni hao”.
But otherwise the Prime Minister has handled the campaign trail without much bother.
We have yet to see an indication that Labor’s campaign is in any real trouble. Polling this week showed it was still comfortably ahead of the government.
That old air of invincibility, however, is definitely beginning to fade.
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