Karen Grogan, who took over the PLUS [Progressive Left Unions and Sub-branches] faction from David Gray in 2019 has confirmed she will seek the party’s endorsement for the casual vacancy, which must be filled this month.

Labor’s state executive met on Monday to open nominations for the seat, with Grogan telling InDaily: “I can confirm I’ll be nominating.”

She has already nominated to the faction, whose endorsement appears a formality given her role as factional convenor, with party sources telling InDaily the state executive would endorse her candidacy.

Grogan is the current national political coordinator with the United Workers Union, and has previously been the CEO of the SA Council of Social Services and a senior staffer for federal frontbencher Mark Butler and former Premier Jay Weatherill.

She said if elected she would intend to see out her term leading the PLUS faction, which is due to expire next year, but “that would be a decision for the executive of the faction”.

While Gallacher was aligned with the Right’s Labor Unity faction, the Left had been handed the power to fill the next senate vacancy under a factional deal brokered in 2018, when the abolition of the lower house seat of Port Adelaide prompted a messy game of musical chairs.

Port Adelaide incumbent and Left faction powerbroker Mark Butler shifted to neighbouring Hindmarsh, whose MP and factional colleague Steve Georganas was given a lifeline to run in Adelaide, with the Right instead filling both winnable spots on the 2019 senate ticket.

Georganas later quit the Left faction to join Labor Unity.

InDaily reported in June on the deal, which could have seen the Adelaide MP ousted within months – as revealed at the time by Maggie Dawkins, whose daughter Alice was embroiled in a messy preselection contest in Spence.

The plan, which has been confirmed by party insiders, could have seen Right-aligned senator Marielle Smith shift to the Lower House to create a vacancy for the Left in the senate.

However, sources say Georganas is now safe in Adelaide, with the unexpected current vacancy saving the party from having to make an immediate call on his future, and giving the Left a second senate seat alongside Penny Wong’s.

The party on Monday also opened nominations for preselection in Adelaide, Hindmarsh, Boothby and Mayo.

Georganas told InDaily he “submitted my nomination for Federal Adelaide yesterday” and was not aware of anyone else running.

“Having said that, it is a democratic process and any eligible party member has the right to nominate,” he said.

Butler will remain in Hindmarsh, while Boothby is set to be contested by St Vincent de Paul Society SA CEO Louise Miller-Frost, as InDaily revealed last week.