Labour Party MP David Cunliffe says he has learnt from his mistakes and is ready to lead the party.
Mr Cunliffe was the final person to put his name forward for the Labour leadership contest before nominations closed on Monday night, joining Grant Robertson and Shane Jones.
He finally declared his hand on Monday afternoon surrounded by supporters in his New Lynn electorate office.
Mr Cunliffe says a lot of caucus colleagues are telling him he has listened and learnt and they are experiencing him differently than they were a couple of years ago.
He say he learnt some hard lessons after his failed attempt to roll David Shearer, but he believes he can win the leadership battle this time.
Mr Cunliffe believes support in caucus is evenly split and told Morning Report he is feeling very comfortable with the level of support he has at the party's base and with its affiliates.
However, he says he is taking nothing for granted as acknowledges he is in a very competitive race against two able colleagues.
He says regardless of who wins, there is a sense within Labour that this contest and the outcome marks a new beginning for the party.
"It'll be a beginning where every member, every affiliate, every MP gets to express their view and once it's over it's settled. And then we go forward as a combined force and we take down the National Government of John Key," he says.
The selection of a new leader is now up to the caucus, party members and the six affiliated unions, and the three candidates are defending the use of taxpayer money to help fund their campaign.
Mr Cunliffe, Mr Jones and Mr Robertson will have 12 candidate meetings around the country.
Their flights will be paid for out of parliamentary funding but other spending, including taxis and phone calls, are a personal expense.
Labour's senior whip, Chris Hipkins, says the taxpayer pays for MPs to do their jobs and travel around the country, and it is a legitimate parliamentary expense.
He says the candidates will be careful to make a distinction between parliamentary and campaign-related expenses.
The largest of the affiliate unions, the Engineering, Printing and Manufacturing Union, says it is yet to decide if it will formally endorse a candidate before its delegates vote.
National secretary Bill Newson says it will make a decision about that this weekend.
The Service and Food Workers Union and the Dairy Workers Union have also not yet decided whether to endorse a candidate.
Former Labour Party chief of staff Stuart Nash says the race is a chance for the party to demonstrate its unity and publicise its policies and presents a fantastic opportunity if it is done right.
Ballot forms will be distributed later this week and the candidate meetings will begin on Saturday.