Former Minister Micheál Martin has emerged as the front runner in the Fianna Fáil leadership race.
Three other contenders - Finance Minister Brian Lenihan, Tourism Minister Mary Hanafin and Social Protection Minister Eamon O'Cuiv - are also bidding to succeed the Taoiseach Brian Cowen.
The deadline for receipt of nominations for the eighth leader of the party closes at 1pm today.
Brian Lenihan is rejecting that the odds are against him securing the post.
"We need to reflect on what's best for the country here.. I have substantial private pledges. I've urged many not to disclose their (voting) intentions (but) I believe there is momentum in my campaign."