Bill Shorten channels Gough Whitlam as he hopes that his time is coming

For Shorten, on his last big occasion of the five weeks, to tap so conspicuously into the Whitlam spirit was a significant decision. For years Whitlam was an icon that Labor aspirants treated with caution, because his story, which started with such promise, went awry. There was no way Bob Hawke, seeking office in 1983, wanted voters to be thinking back to Gough.

But now the Whitlam government's falling apart has faded into history and the hope he represented can be resurrected. Or that was Shorten's gamble (some worry a hubristic one).

Like Whitlam, Shorten is selling a huge bag of promises (including in those familiar Whitlam areas of health, education, environment and infrastructure - climate change is a central addition).

It was perhaps easier to persuade people of the case for change in the late 1960s and early 1970s, when voters weren't so sour and cynical. But on the other hand, angry voters may now be more inclined to deliver punishment to incumbents.

In 1972, Whitlam was claiming his big spending could all be done without increasing tax. Shorten's program comes with its own rigorous payment plan, a much more realistic and responsible approach, but with greater challenges too.

There's another big difference for Labor between then and now. While Shorten plays well to a crowd of the faithful, he is no Gough Whitlam, who captured the public's imagination with genuine charisma. If Labor wins Shorten will deserve massive credit, but no one will put victory down to his personal appeal.

Addressing the more staid setting of a National Press Club audience on Thursday, Scott Morrison observed that the consensus is Saturday's election will be close, which wasn't what people had been writing a few months ago.

Whether the consensus will become the reality we'll know soon enough. But certainly in the run up to the campaign, Labor appeared to be unassailably in the box seat. Now there is more confusion, and a degree of nail biting in Labor circles. Electorates are expected to change hands in both directions.

Morrison has been a much better campaigner than anticipated. This is especially notable because he is offering relatively little - some immediate tax cuts (more than matched by Labor), with further tax relief far down the track.

Morrison's campaign has been all about the negatives, why this is "not the time for change", conjuring up fears about what Labor's tax agenda would bring. It's been focused on caution, the need for people to avoid the unknown in uncertain times.

The Prime Minister is also pitching the ultimate "trust me" message, sometimes wrapped in language smacking of the pulpit or the song circuit.

After dodging most questions at the NPC, Morrison ended by saying if Australians voted for him, they could be "absolutely assured that I will burn for you every day, every single day, so you can achieve your ambitions, your aspirations, your desires".

Just how he would "burn" is, however, something to be revealed in the event of victory.

As a campaigner Morrison has been a natural, partly because he's a "whatever it takes" man and, as the underdog, he figured he'd have nothing to lose.

Shorten exceeded expectations in the 2016 campaign when he was under less pressure. This time he has been competent but patchy.

He's had high spots, especially the set pieces, and his response to the Daily Telegraph's story about his mother.

But there were a couple of glitches, and a bit of tension between the travelling team and campaign head office. And Shorten has been on edge, fearing some strike that might derail his run when the prize is so close.

Nevertheless, Labor's campaign has been well planned and delivered. The initiatives on cancer funding, child care, and the pensioner dental scheme are appealing. The costings have been credible. The fiscal bottom line is convincing economically and savvy politically. But Labor's proposed curbs on negative gearing and franking credits will cost it some votes.

Shorten went into the race the favourite but like the favourite on the racetrack, he is carrying a lot of weight.

This week's polls have been tight but (as with all the polls for literally years) have Labor still ahead.

If Labor is the victor with a narrow majority, Shorten will be anxious to proceed quickly with his ambitious and detailed program.

But he would need to maintain the tight discipline Labor has shown so admirably in opposition, and that would not necessarily be easy. And favours would start to be called in from the unions and others.

The Senate would likely be a challenge to some of the ALP's tax measures, which would have implications for the expenditure side.

If Shorten wins he would be going into office with the most ambitious Labor program since Whitlam. Would it be too ambitious? That's impossible to anticipate.

But - unlike the Whitlam ministry which took over after 23 years of conservative rule - many on the Shorten frontbench would be steeped in previous ministerial experience. And this would be a very important safety catch.

If Saturday's result is a hung parliament (Labor or Coalition) the voters can only blame themselves for delivering a political outcome that would make policy outcomes more difficult to bring about.

A re-elected Morrison majority government would be a big question mark. There is not a comprehensive blueprint on the record, just a hungry PM on display. "I'm just getting started," he tells us. "The hunger for Australia and achieving the aspirations of Australia, it is burning deep within me."