Staying on message and mobilising supporters will be the primary challenge facing the Greens as the new leaders brace for their first full day at the helm.
Senator David Shoebridge won the leadership and fellow upper house member Steph Hodgins-May was selected as his deputy after an internal party vote during a policy meeting in Sydney on Wednesday.
Before the vote, the senators vowed not to "reform Labor, but to replace them".
The influence of the UK Greens movement was impossible to miss, Monash University political science lecturer Nathan Fioritti said.
"This is lifted almost entirely from (UK Greens leader Zack) Polanski's rhetoric," Dr Fioritti told AAP.
"I don't think the message is a new one.
"Whether a new leader can give new energy to that push and achieve cut through is probably the the challenge."
Since the federal election in May 2025, One Nation has surged in opinion polls, consistently eclipsing the coalition with first-preference votes in the high 20s.
The Greens have barely budged from their haul of 12 per cent at the last election.
In the same period, the UK Greens under Mr Polanski have lifted their share from nine per cent to peak of 18 per cent at local government elections in May.
"It hasn't shifted to the point we would obviously like to see," Senator Shoebridge told ABC's 7.30 on Wednesday when quizzed about the Greens' languishing vote share, adding concentrated media ownership might be partly to blame.
"This is the incredible magic sauce of politics ... to find a way around a mainstream media that doesn't want the message to be heard."
Dr Fioritti said Australia and the UK faced similar political landscapes featuring a Labor party in office with a large majority and an increasingly disenfranchised voter base turning to minor parties particularly on the far-right.
"This is an opportunity for the Greens to refresh the leadership and prioritise presenting the party as a progressive or left wing alternative to One Nation for those disaffected voters," he said.
Senator Shoebridge pledged to tackle the growing popularity of One Nation, blaming Labor for creating a space for Pauline Hanson's resurgence without the ability to do anything about it.
"People aren't interested in some kind of incrementalist politics or some kind of smart messaging, they are angry," he said on Wednesday, defending his party's sometimes uncompromising brand of politics.
Former MP and current executive director of the Green Institute, Max Chandler-Mather, issued an open letter on Tuesday to the party before the leadership vote.
In it, he urged the party to follow the lead of its UK and New Zealand counterparts and introduce a vote for all members of the Greens to determine the leader.
"Direct member election of the leader won’t achieve on its own. But I fundamentally believe it is a crucial step towards building the movement we need," Mr Chandler-Mather said.
Former deputy Mehreen Faruqi echoed the call in a post to social media in the hours after the leadership announcement.
