A Tasmanian Labor leadership hopeful says the party needs to "stop the domination of the hard left" in order to be competitive at the next election.
Braddon MP Shane Broad and former deputy David O'Byrne will contest a party ballot for the top job after Rebecca White decided to step down at the weekend.
Labor has been left to lick its wounds after the May 1 state election, with the Liberal government winning a historic third successive term.
Dr Broad, who announced his intention to run for the leadership on Monday, says there is a growing frustration among the party's moderate voices.
"The only way to win votes off the Liberals is from the centre of the political spectrum. That's why I'm putting my hat in the ring," he told ABC radio.
"There needs to be a rallying cry for the centre of the Labor Party to get active and to stop what is the domination of a hard left faction group of powerbrokers that I believe have delivered three election losses."
It is not known when the ballot of party members and parliamentarians will be held but the process could take weeks.
Labor has pledged to undertake a review of its state election performance after the party suffered a swing against it but still retained nine of the 25 lower-house seats.
Dr Broad said he would campaign for federal party intervention, as the left faction had "rewritten party rules" and had "veto power" which prevented moderates getting leadership positions.
"I learned a lesson a very long time ago on the school bus. The only way to stand up to bullies is to start swinging," he said.
"You might cop a few hits but the bullies will think twice next time."
Labor needed to reconnect with voters who have jumped ship to the Liberals, Dr Broad said, adding the party had to do a better job of defending Tasmania's traditional industries such as forestry.
Mr O'Byrne, who is considered likely to have the required support, said he welcomed the ballot process.
Braddon MP Anita Dow has been elected as Labor's new deputy leader and will be acting leader until the ballot.
Labor's election campaign was riddled with bitter infighting, particularly around the pre-selection of Franklin candidate Dean Winter, who was initially blocked from running but went on to win a seat.
Australian Associated Press