Finance Minister Brian Lenihan and Minister for Tourism, Culture & Sport Mary Hanafin have formally announced their candidacies for the leadership of Fianna Fáil.
Mr Lenihan has said that the Opposition is keen to have the shortest possible campaign for the General Election.
He said the election will be enormously challenging for Fianna Fáil, but insisted it will 'take the fight to every corner of the country.'
Mr Lenihan said that people are anxious that there is a leadership contest and the fact three other people have declared their interest in the role is welcome.
At a news conference in Dublin, Mr Lenihan said he wanted to release the energy of young people in the party and he said the party must shift to a new generation.
He said he is determined to hold any new Government to account if Fianna Fáil is in opposition, he said it was not in the interest of the country to have an opposition which is not strong and robust.
Mr Lenihan said leadership is about substance and whilst communications is crucial, leadership is the most effective method of communication.
The minister said mistakes have been made by his party and everyone must take responsibility for those mistakes.
Mr Lenihan said the Fianna Fáil that he would lead would be 'of a more decisive character.'
The minister said he would build a sustainable economic recovery as leader of Fianna Fáil and would prioritise national competitiveness.
He said he would also lead a radical reform and transformation of the political system with a smaller Dáil and Seanad, and with ministers being appointed from amongst the membership of the new smaller Seanad.
The 51-year-old, who has been battling cancer, said he had sought advice of doctors who had assured him he is more than able to meet the challenges associated with leadership.
He said his tumour has reduced substantially and energy levels are restored. Mr Lenihan said he is immensely grateful to the Irish people for the goodwill shown in the last year or so.
Minister of State Sean Connick has confirmed he will be supporting the Finance Minister’s bid. The Wexford TD said he had considered contesting the leadership, but decided instead to back Mr Lenihan.
Mary Hanafin would 'love to lead'
Meanwhile, Minister for Tourism, Culture & Sport Mary Hanafin has said she would love to lead a new Fianna Fáil party which was new and renewed, where young people and women were encouraged to take part.
Ms Hanafin said she had rung around a number of her party colleagues to get their views before she decided to go forward as a candidate for the party leadership.
Minister Hanafin said she was being proposed by fellow Minister Pat Carey and being seconded by Tipperary North TD Máire Hoctor.
Asked about her stance over the confidence motion in Brian Cowen's leadership, she said she had voted against the motion and had indicated to Brian Cowen that she would be doing so.
However, she said that this weekend we are seeing that there is a difference between the leadership of Fianna Fáil and the leadership of the country, and she believed her position had been vindicated.
She said she was asking other Fianna Fáil deputies not to declare publicly who they were supporting because she did not think that was necessary.
The Minister of State for Science, Technology and Innovation, Conor Lenihan, has tonight confirmed he does not intend to put his name forward for the Fianna Fail leadership
Yesterday, former Minister for Foreign Affairs Micheál Martin and Social Protection Minister Éamon Ó Cuív publicly confirmed that they will be candidates too.
Speaking on RTÉ's This Week, Minister Ó Cuív said as Fianna Fáil party leader he would address the issues of social cohesion in the country, to provide a society in which people feel equal and are equal
He also said Fianna Fáil needed to be rebuilt parish by parish.
Minister Éamon Ó Cuív said he is satisfied the he has significant support within the Fianna Fáil parliamentary party for his leadership bid.
He said one his first priorities would be to rebuild the party from the ground up, especially in urban areas.
Mr Ó Cuív said it is important that the Fianna Fáil party now outlines ‘a clear programme for the people showing how to get out of the current difficulties and how we are going to protect the most vulnerable in society.’
In a letter to TDs Éamon Ó Cúiv said that he reflected a Fianna Fáil that saw economic progress as a means of improving peoples lives and a wider view of politics that balanced economic growth with cultural community and social progress.
The new leader will be elected by Fianna Fáil TDs in a secret ballot on Wednesday afternoon.