Gerry Brownlee was elected her deputy, ensuring both continuity in the party's election campaign team just nine weeks out from election day, and a duo comprising two of the most senior and experienced survivors of John Key's 2008-to-2016 prime ministership.
Brownlee replaced Bridges's deputy, Paula Bennett, as campaign manager and it is understood that key advisers Matthew Hooton and Tim Hurdle, both of whom were appointed by Muller, are likely to continue to work on the campaign.
It was unclear this evening who else put themselves up for the role, although Bridges was believed to have been willing to stand again and there were rumours reported by Newshub during the two hour caucus that Mark Mitchell – who has challenged before – had formed a ticket with senior whip Louise Upston.
Collins first entered Parliament as an opposition backbencher in 2002, and held a number of roles in the 2008 government led by Prime Minister John Key, including Police Minister, where she earned the nickname "Crusher", a reference to her policy of crushing cars seized from criminals and an emblem for her steely political persona.
In an auto-biography published this month, Collins says on the first page of chapter one that "there is nothing quite like a lost cause to get me interested in it" of her initial involvement in the National Party in the 2002 election campaign, which then leader Bill English lost heavily, securing just 21 percent of the party vote.
A page later she comments that "the time to get involved (in politics) is when others are fleeing. That's when we can make the biggest difference."
She also writes at length later in the book about the need for a political party to have "friends" in an MMP electoral system – a clear swipe at Bridges's strategy of ruling out working with NZ First, which National would need to do if it were to have any hope of governing after Sept. 19 – and assuming stronger poll results for both National and NZ First than at present.
She says that both the Labour Party and its opponents had underestimated Jacinda Ardern's political potential, but that "today's Labour Party is not a credible threat without Ardern."
Roy Morgan NZ released results for the first time from a poll taken over the course of last month showing Labour at 54.5 percent support, sufficient to govern alone.
The poll covers the first few weeks of former National Party leader's short leadership and records 27 percent support for the party, consistent with the sub-30 percent support levels seen for Simon Bridges, the leader Muller deposed.
"National's decision to change leaders in late May has failed to improve their support, with Prime Minister Jacinda Ardern set to be re-elected with an increased majority," said Roy Morgan's chief executive, Michelle Levine.
The same Roy Morgan poll gives NZ First, Labour's current coalition partner, just 1.5 percent support, well below the 5 percent threshold guaranteeing the party a return to Parliament after the general election scheduled for Sept 19.
Roy Morgan scored the Green Party at 9 percent, higher than most other publicly published opinion polls but consistent with its showing in other polls by the Australian-based research group this year.
The ACT party achieved the 5 percent threshold required for guaranteed parliamentary representation in the Roy Morgan poll.
If the poll were translated into votes on election night, Labour would be able to govern alone with 69 seats in the 120 parliament, likely supported in principle by the Greens, with 11 seats and National with just 34 seats compared to 56 at present. ACT would have six seats on that outcome.
The most recent, undated poll circulating from Labour's pollster, UMR, puts Labour at 53 percent support, National at 32 percent, the Greens at 5 percent, NZ First at 4 percent and ACT at 3.3 percent.
