The memo from Labor’s campaign headquarters on the first full day of the marathon 55-day campaign sounded a note of caution: “Labor is the underdog this election – Mr Turnbull starts with a 20-seat head start.”

Indeed he does; but if there is a swing that some polls are picking up of about 4.5 per cent against the government, enough of those seats will be swept into political oblivion. Three scenarios are all credible: a tight Labor victory, a tight Liberal victory or a hung parliament.

After the first week of the longest election campaign in 50 years, the polls still have it at 50-50, according to analyst Andrew Catsaras. There is certainly a swing against the government; the question is what will happen to it between now and polling day. The bookies have Labor at longer odds but that could just as well mean they take a bath on July 2.

The mood at Labor’s CHQ is upbeat. Campaign director George Wright is in much better shape this time than he was in 2013, when months of planning and half his staff disappeared after Kevin Rudd staged his counter-coup against Julia Gillard. The disconnect between the Rudd plane and central office became more and more obvious as the campaign rolled on. Though Tony Abbott’s Liberals handed Labor one of its biggest hidings, the party was grateful much of its talent survived the bloodbath.

There is a lot of luck and relativity in politics but the truth is what can appear as good fortune is also the result of canny hard work. Bill Shorten’s luck is the funk Malcolm Turnbull seemed to go into for the first six months of his prime ministership. The Labor leader filled the void with policies tailored to meet concerns in the electorate and the expectations of contemporary Australia.

Labor hard heads welcome the fact that the tight polling – a trend that began building in January – means the campaign will be crucial to success. One of the reasons for this situation is the gradual erosion of Turnbull’s standing with voters. “Disappointment” rather than “anger” is the mood here. But Labor research has picked up a new category of voter: not chardonnay socialists or the cafe latte set but their successors, “Q&A Turnbull voters”. These are the soft, middle-of-the-road urban voters who liked what they saw of the pre-prime ministerial Turnbull on the ABC TV panel show.

Sydney’s Daily Telegraph has identified a bigger threat to the nation than Labor, and that is the Greens.

Here was the suave, leather-jacketed modern politician with intelligent views on climate change, inclusive views on marriage equality and compassionate sentiments on asylum seekers. They appear not to have lost complete faith in this Turnbull reappearing after an election win. This is one explanation for Labor not doing as well in the metropolitan marginals as it must do to win. Ironically, the further away from the CBD the less this sentiment is holding up. Regional voters appear to be more disappointed with the prime minister, which explains why Shorten spent most of week one in regional Queensland.

When Liberal MPs came back to Canberra for the special sitting of parliament, they swapped notes on what they were hearing in their electorates. A common experience was that they could not detect any mood for change or anger with the Turnbull government. But the other common theme was constituents hoping that after the election Turnbull would return to being himself.

Shadow treasurer Chris Bowen, one of the Labor talents to survive the Abbott landslide, impressed with his budget reply at the National Press Club. He came with a coherent economic story and some killer lines, characterising the three years of the Coalition government as a series of false starts and missed opportunities.

Bowen said Turnbull’s assessment of Abbott’s failed economic leadership is something that has not been addressed: “Debt up, deficits up. Confidence down, living standards down.” There’s no doubt that if his reading of the government’s re-election pitch is shared by voters then Turnbull will be in diabolical trouble. Bowen said it amounts to this: “Please let us have another chance. We have wasted three years. But we’ll try harder next time.”

It is 85 years since a first-term federal government was thrown out. But Victoria and Queensland state elections show that voters are more interested in performance than in precedent. And they are able to make up their minds despite ferocious anti-Labor campaigns mounted by the mass circulation Murdoch tabloids.

This time around, Sydney’s Daily Telegraph has identified a bigger threat to the nation than Labor, and that is the Greens. Midweek it ran a front-page mock-up of a campaign button featuring a stylised head of opposition frontbencher Anthony Albanese with the slogan “Save Our Albo”. This true believer, readers were told, is in the fight of his political life “with a Greens radical who wants to overthrow capitalism”. The Telegraph seems somewhat conflicted in its usually pro-Coalition coverage. The day after the Morrison budget it ran a series of cameos to show how nasties in Joe Hockey’s 2014 budget have been left in place and will cost a range of families thousands of dollars in lost benefits and payments.

The conflict may be born of its ambivalence, if not outright hostility to Malcolm Turnbull. Two of its high-profile columnists are on either side of the divide. Miranda Devine coined the phrase “delcon” to nail delusional conservatives who hanker for a return of Abbott. While her stable mate, Andrew Bolt, without Abbott at the helm, is bereft of any leader he can support. He has joined the campaign of the right-wing think tank the IPA in slamming the Turnbull government’s retrospectivity in winding back generous tax concessions for millionaires. He and the institute are strange bedfellows with an opportunistic Labor Party on this.

The shadow of Abbott fell on Turnbull and Fiona Scott, the Liberal member for the marginal western Sydney seat of Lindsay, this week. Leaked emails from Abbott supporters in Warringah condemned her for deserting the former PM and said they would not help her campaign. A Turnbull doorstop was disrupted when journalists were more interested in her fessing up to her leadership vote. She wouldn’t, but she did say she didn’t need the outside help now or last time. A similar leak targeted Peter Hendy, the Liberal member in the bellwether seat of Eden-Monaro. He was a key player in last September’s coup. Again, the threatened boycott was hollow but both instances are an unhealthy undercurrent feeding into perceptions of divisions that could threaten the government.

The Brisbane Courier-Mail helpfully carried a story that Abbott was heading for Queensland and would campaign in seats that “so far Malcolm Turnbull has avoided”. One just so happens to be the Mackay-based seat of Dawson. Its sitting member is the ultra-conservative George Christensen, who sits in Canberra as a National. Christensen is quoted as saying Abbott is popular in the electorate and could connect on “heartland issues”. It doesn’t take much imagination to see what they would be: the campaign against same-sex marriage or a rerun of the carbon tax scare based on calibrated climate change denialism.

Liberal campaign headquarters did a lot of hard work researching Labor candidates and their attitudes to the ALP’s asylum-seeker policies, combing social media pages for signs of dissent. It flushed out seven who had rejected Labor’s policy, including the candidate for the Townsville-based seat of Herbert. A picture of Cathy O’Toole retrieved from her Facebook page was sent to the travelling media’s smartphones. She was part of a protest earlier this year outside the sitting LNP member’s office. O’Toole was holding a placard that read, “Let Them Stay.” That was before she was endorsed as the ALP’s candidate. Shorten’s doorstop was disrupted as the press pack peppered O’Toole on her support for the policy. She obliged, stressing its humanitarian elements.

Shorten stepped in, stressing its less-than-gentle aspects: boat turn-backs and offshore processing. The latter has proved a euphemism for indefinite, harsh detention, but it is bipartisan policy. There are unhappy campers about it in both the major parties.

The Greens muscled their way into the week by seizing on the tight polls to announce they were ready, willing and able to back a minority Labor government. Turnbull grabbed the gift with both hands warning of a return to the years of the Gillard minority government with its centrepiece broken promise of a carbon tax. Shorten dismissed the suggestion: “Tell them they’re dreaming.” His colleagues almost said never ever. But ruling out a “coalition” is not ruling out an arrangement with individual Greens for support.

That’s what happened in Tasmania in the last Labor–Greens accommodation. Now senator Nick McKim and his colleague Cassy O’Connor were members of cabinet pledged to support supply and nothing else. But Tasmania also provides the nation with another option. From 1996 to 1998, Liberal premier Tony Rundle led a minority government supported by the Greens under Christine Milne.

A Turnbull minority government with Greens ministers would be something. It is probably the only way the “Q&A voters” will get the Malcolm Turnbull they really want.