Tuesday evening at a bowls club in one of Sydney’s affluent northern beachside suburbs. Bland 1960s architecture, a fading picture of a young Queen Elizabeth on the wall, along with the usual plaques and honour rolls. It seems an unlikely incubator of progressive activism.

Before this night, probably the most radical action contemplated at this venue was the decision some years ago to allow barefoot lawn bowls. It has never hosted any kind of political meeting.

Nor do the couple of hundred people gathered in the room look like members of what one right-wing tabloid recently called a “leftie war machine”. The dress is neat casual – lots of men in polo shirts and women in nice frocks with neat coiffures – and the median crowd member appears to be comfortably retired.

The foot soldiers of the GetUp! campaign to oust Tony Abbott from the seat of Warringah defy the caricature drawn by their opponents. They look like nice, ordinary, middle-class members of the affluent northern beaches community – albeit somewhat older than the average age of 39. They do not appear to be wild ideologues.

These men and women have turned up for what GetUp! calls a “barnstorming session”, and after an hour or so of motivational talk from organisers they will be asked to sign up to knock on doors in various suburbs, to try to persuade people to “vote Tony out”.

This event is one of six similar “barnstorming” gatherings held in cities around the country in the first three days of this week.

Person-to-person interactions, the Warringah crowd is told, are proven to be the most persuasive form of electioneering. Already, local volunteers like them have knocked on 13,000 doors, or about 20 per cent of the electorate’s homes. Some 88,000 phone calls – live ones, not robocalls – have been made.

And there is progress to report: Abbott is now slightly behind in the polls, the organisers say. That is not cause for complacency, though, for there remain many undecided voters. According to GetUp!’s metrics, compiled from the debriefing sessions after their efforts so far, “soft non-Abbott” voters still outnumber soft Abbott voters 3-1. Those soft voters have to be convinced.

“There are seven key focus points,” Oosting says. “Six are people from the hard-right faction. We’ve tried to go after people who are the leaders of it.”

The potential volunteers are reminded of “the horrible sinking feeling” they had when Donald Trump defied the polls to become United States president. They are reminded that the Liberals got much closer to winning the Wentworth byelection than polls predicted.

They are told that Abbott has a $1.4 million war chest with which to buy votes, but that people power can overcome money, if the people are sufficiently dedicated. But they have only four weeks to do it.

They are further informed that GetUp! has tested its messages and found the most persuasive arguments to use against Abbott relate to his reactionary social attitudes on issues such as same-sex marriage, his suggestion the Liberals should give preferences to One Nation, and his climate change denialism.

Above all, it’s about climate change. That is the No. 1 reason people in Warringah are deserting Abbott, the organisers stress.

The crowd hears testimony, too, from local veterans of the doorknocking campaign who will lead the various groups. One says it has become his major post-retirement activity and, he considers, his “civic duty”. Another is the grandmother of two young children, and is desperately concerned for their future if action is not taken on climate change. Another speaks of the personal satisfaction of making converts.

The prospective volunteers are promised scripts and training in how to engage. They are assured of support “every step of the way”.

The GetUp! crew are good at working the crowd, and by the end of their pitch audience members are literally stamping their feet with enthusiasm. Then 15 or so “hosts”, as group leaders are called, are paraded across the stage, each carrying a sign with a date, time and location to meet for a weekly three-hour doorknocking effort in one suburb or another. Each host says a few words, then they disperse to different parts of the hall with their clipboards, ready to take down names and contact details. By the end of the night, 91 new volunteers sign up, in some cases with multiple groups, to go out doorknocking every week until the May 18 election.

Finally, at the door, the newly engaged activists are given corflutes, stickers and other campaign material before they head out into the warm evening with a babble of happy chatter and a new sense of purpose.

It all spells big trouble for Tony Abbott, not only because so many GetUp! volunteers are working against him but because they are so close in their personal characteristics to his support base. The polls tell us the only section of the electorate in which the Liberals still enjoy a significant advantage is with those aged over 55. And that is the exact demographic of these new volunteers, and the larger group with whom they are networked, and the even larger group that will be the major target of their doorknocking efforts.

The GetUp! campaign is not about telling people whom they should vote for, only whom they should vote against. During Tuesday night’s proceedings there was no endorsement – or even mention – of any other party or candidate. Their aim is not to encourage votes for Labor, or the Greens, or even the front-running independent candidate, Zali Steggall. Their aim is to get votes for anyone but Abbott.

Which is in line with the organisation’s long-established goal – not to spruik for any particular party, but to exert pressure to move politics in general in a progressive direction.

The conservative parties have long claimed GetUp! is but a front for Labor and the Greens, and have repeatedly made representations to the Australian Electoral Commission to have it declared as an associated entity of the two parties. The AEC has repeatedly found the group is not. There are no formal links in terms of funding or personnel. On occasion, GetUp! has worked with the Liberals on some matters and is not averse to criticising both major parties when the issue demands it – as with the bipartisan failure to stop the Adani coalmine project.

Unlike political parties, which work towards the quantitative goal of getting as many of their people elected as possible, GetUp! has a qualitative goal – getting those it considers the greatest impediment to its progressive agenda unelected.

“Our goal simply is to remove the hard right,” says GetUp! national director Paul Oosting.

And it has a fair record of success.

At the last election, in 2016, the organisation targeted 12 Coalition seats. Five of them fell – Bass and Braddon in Tasmania, Macarthur and Macquarie in New South Wales, and Mayo in South Australia.

Of course, there were multiple factors involved in those results. Labor and the unions also put big resources into a number of those seats. But in almost all of those where the activist group campaigned, the swings against the government were far higher than the national average. The godfather of the hard right in Tasmania, Senator Eric Abetz, had no doubt the “grubs” of GetUp! were largely responsible for conservative losses in his state.

Perhaps the greatest evidence of its electoral power, though, was the result in Peter Dutton’s seat of Dickson in south-east Queensland. Before the 2016 election, Dutton enjoyed a relatively healthy margin of 6.7 per cent.

“No other major group was working in that seat,” Oosting says. “The Labor Party and the unions didn’t see it as marginal, so they weren’t very active. Yet the swing there was double the statewide average.”

Dutton’s margin was cut to a skinny 1.7 per cent.

In retrospect, Oosting wishes GetUp! had put more resources into Dickson, but at the time even he half-believed Dutton was unassailable. Had they worked it harder, maybe they could have achieved a result such as the one in Bass, where the swing against the right’s Andrew Nikolic was 10 per cent.

Dutton went on, as Oosting notes, to become the leader of the hard right, to “design the marriage equality plebiscite to fail” and eventually to orchestrate the leadership coup against Malcolm Turnbull.

That still rankles Oosting. It is part of the reason he considers the 2016 campaign to be an indication of the disruptive potential of his organisation, but also, frankly, something of a failure.

While GetUp! achieved “a lot of notoriety” and succeeded in knocking off some – mostly minor – members of the conservative right, it did not result in the change the group had hoped for.

“Our objective as an organisation is really about getting policy action in areas our members care about. And we have to be realistic in admitting we have not got that policy change. When we look at an issue like climate change, Australia has gone backwards, not forwards.”

This election, the effort will be much bigger, much more concentrated and technologically sophisticated.

“There are seven key focus points,” Oosting says. “Six are people from the hard-right faction. We’ve tried to go after people who are the leaders of it.”

Three of those six are senior ministers – Home Affairs Minister Dutton from Queensland, Health Minister Greg Hunt from Victoria and Attorney-General Christian Porter from Western Australia. The others, Tony Abbott, Kevin Andrews and Nicolle Flint, are influential backbenchers.

They were selected as targets for a combination of reasons. These MPs are not necessarily the lowest-hanging fruit in terms of electoral margins, but they are all vulnerable. Most importantly, they are right-wingers and were prominent members of the Dutton leadership insurgency. Geography was also a consideration. Flint, for example, is something of a political bit player, but she’s from South Australia.

The seventh target is Treasurer Josh Frydenberg, who is not hard right and was not a Dutton supporter in the leadership coup. Why him?

“Our members voted on that,” Oosting says. “We also look at the issues alignment. Climate and Adani [voted the most important issues by GetUp! members] are very big in Kooyong.”

Counterintuitively, elector concern about climate and the environment tends to be particularly strong in some of the most blue-ribbon Liberal seats, such as Kooyong, Wentworth and Warringah. As does GetUp! membership.

And while Frydenberg looks safe on paper – with a healthy margin of 12.8 per cent – at last November’s Victorian election there were huge swings against the Liberals in the state seats that overlap Kooyong.

GetUp! will hand out how-to-vote cards in about 30 seats this election, but those seven “are where we are devoting 95 per cent of our resources, where people will be doorknocking, phone banking, and where most of our ads will be,” says Oosting.

Those resources are considerable. GetUp! is transparent about its finances, updating them in real time, something that can’t be said of political parties. As of Thursday, it had received 617,000 separate donations from almost 50,000 people, who gave an average $20. In all, its election war chest totals more than $12.7 million.

The number and size of donations has dramatically increased in the run-up to the election. In the past week alone, almost $600,000 in donations was made, with the average donation size up to $36.

But money, says Oosting, is not the key metric. It’s people.

“We have more supporters than the major political parties,” he boasts.

At the start of this week, some 7000 of them had volunteered for electioneering actions of various kinds, and their number is growing quickly.

Technology is the great force multiplier. Video conferencing of volunteers happens “basically every night”, says Oosting. The virtual campaign launch was “attended” via video by about 1600 people. A teleconference this week was attended by 2000.

In 2016, GetUp! activists made 216,000 phone calls to electors; this time, the goal is one million. Last time, volunteers gathered in GetUp! offices to make those calls, says Oosting. This time they can do it from their homes, on their own phones. They dial into GetUp! and are redirected into a target electorate, with GetUp! picking up the phone bill.

On Tuesday, when The Saturday Paper visited the GetUp! head office in Sydney, phone campaign plans were being nutted out so people all over the country could better hit the target electorates in a co-ordinated way. Volunteers in Perth, for example, might ring the voters of Kooyong on a particular day, and vice versa on another day. The reason: their technology connects faster if many are calling into one area at one time.

While better technology makes the operation more efficient, the essence of the strategy is still human contact. These are not robocalls; they are conversations. Volunteers are trained and provided with scripts, but Oosting prefers to term them “conversation guides”.

“It’s not like reading out a script saying, ‘Here’s what you should do,’ ” he explains. “We encourage our people to do more listening and answering than talking. And trying to make a connection about values.”

In accordance with the organisation’s policy of transparency, the conversation guides are made public on the GetUp! website.

On Tuesday, Oosting professed amusement at stories that had run in various media, boasting of “exclusive” revelations of the calling guides. “They have been available on our website for weeks,” he said.

But amusement cometh before a fall. The next day, it emerged the conversation guide for Frydenberg’s seat contained a serious error of fact – it accused the treasurer of having been “part of the coup” against Malcolm Turnbull, which he was not.

Oosting was blindsided in an interview with Jon Faine on ABC Radio in Melbourne and offered what could only be called a lame defence. In his fluster, the GetUp! boss got Frydenberg’s portfolio wrong. Twice. The Sydney Morning Herald and The Age called it a “car crash” interview. The Murdoch press and right-wing radio were much nastier.

When we spoke to him on Thursday, Oosting was much chastened but portrayed the misrepresentation as a dumb error rather than a deliberate lie. For the other six Liberals the organisation is targeting, the talking point in relation to the leadership coup is true. Oosting says it was just cut-and-pasted into the Kooyong script. After the Faine interview, it was quickly removed.

While the incident was embarrassing, it’s unlikely to be of consequence to GetUp!’s campaign beyond Kooyong. The cash donations are still flooding in – another $60,000 on Thursday alone. The volunteers continue to sign up in droves. The doors are still being knocked on. The “phone parties” still proliferate in lounge rooms around the country.

As much as they pretend otherwise, the hard right of the government must know they face a formidable opponent in GetUp!

Speaking on Sky News on Monday, the faction’s Victorian godfather, Michael Kroger, affected unconcern.

“I wonder whether GetUp! are fading in this election?” he asked. “I don’t feel that GetUp! are the palpable force they were in the last election. I just don’t feel a potency in the GetUp! message that I saw three years ago…”

Had he been at that bowls club on Tuesday, and seen that foot-stamping, clapping, cheering crowd, he might not be so dismissive.