Cowdenbeath MSP Alex Rowley says he's running to become deputy Scottish Labour Leader
The former Fife Council leader has previously said the party needs to distance itself from the UK party, and even consider full fiscal autonomy for the Scottish Parliament.
He faces competition from Glasgow City Council leader Gordon Matheson and North East Scotland MSP Richard Baker.
Current leader at Holyrood, Kezia Dugdale MSP, and Eastwood MSP Ken Macintosh are the only two so far running to replace Jim Murphy.
Meanwhile fellow Fife MSP Claire Baker is Campaign co-Chair for Ms Dugdale's bid for the leader's role.
She said: “The Scottish Labour party needs a leader who can win back the trust of the people of Scotland. We need to look to a new generation and have a single focus - securing a more equal and socially just Scotland. Kezia works day in and day out to achieve this and she is without doubt the person for the job."
Kezia Dugdale said it was "an honour" to have secured the support of 30 of Scottish Labour’s 41 parliamentarians on the day nominations opened.
“We know politics in Scotland has changed fundamentally and the Scottish Labour Party have only one chance to get it right.
“But this Leadership election isn’t just about transforming Scottish Labour, it is about stepping up and regaining the trust of the people of Scotland.
“My campaign will be reaching out to people whose support Labour has lost, and those who’ve never voted for us before - because our values are as relevant today as they have ever been.
“Scottish Labour has been the insurgent force before, pushing back against the political establishment and winning great victories and profound social change. To win, we must adapt to new challenges and opportunites, and new barriers to progress. As Scottish Labour Leader that’s what I would work for every single day.”
'More open, more transparent'
The other leadership candidate, Ken Macintosh MSP, said: “May was a terrible defeat for Scottish Labour and I know that many MSP colleagues’ heads are down. Some are looking to steady the ship but we must be honest with ourselves and realise that if we want to win again, if we want Scotland to trust us again, more of the same will not do – we need a new approach. The decision of who should lead our party and make the fundamental change we need will not be decided by elected members; this crucial decision over the future of our party will rightly be made by Scottish Labour members and supporters right across Scotland.
"This is our moment to show our resilience, to reclaim our party and to show Scotland we have listened to the very loud message that they sent us in May, and at previous Scottish elections too.
"I am pleased the SEC adopted my proposals to reform the leadership process ensuring our next leader will be elected using one person, one vote and that Labour supporters across Scotland will be given the opportunity to have their say on who should lead Scotland’s Labour Party. I am also delighted that the party supported my calls for the next Deputy Leader to come from Local Government and I hope, and encourage, as many Council colleagues to consider putting their name forward.
"Scottish Labour needs to become more open, more transparent and we must shift control of our party from the corridors of power to the communities of Scotland – I believe a healthy, robust leadership contest which listens to Scotland will start that process.”