Ms Heseltine just missed out on a place in Labor's election line-up for the Woden-Weston seat of Murrumbidgee, coming sixth of nine candidates.

Murrumbidgee was a closely contested race, replete with factional shenanigans that brought an early end to the political career of Labor's deputy leader, Simon Corbell, and possibly also sealed Ms Heseltine's fate.

But she remained upbeat about the outcome on Tuesday, saying she was "genuinely not upset" that she missed out and was heartened by support for her across the factions, and by the closeness of the contest despite her relatively short membership of the party.

The Fluffy asbestos battle was "infinitely harder".

"I was exhilarated by being part of the most hotly contested preselection process in Labor's history. Having so many Labor candidates in the field only bolstered democracy," she said.

"Politics is not an arena for the faint-hearted. When I joined the party I knew what I was getting into and I've been astonished by the support I've received from rank and file members across factional lines since I joined.

"I made it clear from day one that I was an unaligned member and the fact is I've drawn people from the left and right factions into the arena with me."

Ms Heseltine lost despite some senior party members regarding her as one of the strongest candidates in the preselection field.

But the Murrumbidgee preselection was coloured by factional deals. The left dumped Mr Corbell to an unwinnable third spot on its ticket, prompting Mr Corbell to announce he would leave politics at the next election. In recent weeks, his dispute with the faction deepened when he resigned from the faction, leaving him able to vote freely in the preselection without being tied to the left ticket.

The left's decision to put the unaligned Mark Kulasingham in third spot and the right's Chris Steel in fourth was also intriguing, sending a message about the faction's view of Ms Heseltine.

For her part, Ms Heseltine will not discuss the left's decisions, nor criticise the factional system, but said she said she was unaligned because she believed "there should be one faction called ACT Labor".

She would not have been eligible to stand were it not for a rule change at the recent ACT Labor conference allowing people to stand with just one year's party membership instead of two, and she points to the rule change as showing that Labor "shares my appetite for positive change".

"Some sensible heads got together and they realised it was an artificial barrier to new blood," she said.

The lesson of the preselection was that winning was about building long-standing relationships in the party, she said. She would not say whether she planned another tilt at politics, but said she would turn her energy to building a force of unaligned party members.

A mother of two young boys and a lawyer with the the Commonwealth Attorney-General's department, she plans to study for the bar exams, and in the long-term to build a practice in the areas of law which interest her, including equity, commercial, public and administrative law. She is also active in the ACT restorative justice network.

As for the fate of Mr Corbell, Ms Heseltine said he had inspired her to join the party in his preparedness to make big decisions on the "dreadful legacy" of Fluffy asbestos. He was "a statesman and a visionary and by far our most profound loss", she said.