The Australian Greens are confident of snaring the federal seat of Batman in the upcoming by-election, but face a tough fight against prominent union boss Ged Kearney.
Sitting Labor MP David Feeney resigned from parliament on Thursday after failing to find evidence he had renounced his British citizenship, making him ineligible to sit in the lower house.
ACTU president Ged Kearney is considered a near certainty to be the ALP candidate for Batman, which could be held as early as March 10.
The Victorian branch of the Labor Party has referred the candidate preselection process to the national executive of the ALP.
A candidate is expected to be locked in over the weekend, to be ready to hit the hustings on Monday.
Greens leader Richard Di Natale thinks his party is in with a real chance to pick up the marginal seat in Melbourne's inner north from Labor, which would give it two spots in the House of Representatives.
"There are so many things that the people of Batman will get an opportunity to vote on and I really look forward to the campaign," he told ABC radio on Friday.
The Greens will campaign on issues such as climate change, the Adani coal mine in Queensland, rising inequality and a more humane approach to immigration issues.
But Labor frontbencher Anthony Albanese thinks his party is capable of retaining Batman because it will offer a strong candidate.
"We are in a position as the alternative government that the Greens will never be," he said.
"They can say whatever they like, they can't achieve things because they won't be sitting on the government benches."
Greens candidate Alex Bhathal has run in each election for the seat since 2001, barring 2007.
She won the primary vote at the last federal election but Mr Feeney clung on after preferences, taking Batman with a margin of one per cent.
The Liberals are yet to say if the party intends to run a candidate and cabinet minister Mathias Cormann refused to buy into questions of whether they would.
"Batman historically has been a safe Labor seat - under Bill Shorten it's obviously become less safe," he told Sky News.
"It's now a contest principally between Labor and the Greens."
A Liberal candidate would be a major boost for Labor which recently lost a state by-election to the Greens in Northcote, which makes up part of Batman.
Senator Di Natale said while Ms Kearney was a good person, she would advocate "bad policies".
