Senator Fiona O'Malley has launched her campaign to succeed Mary Harney as the leader of the Progressive Democrats at the party's headquarters in Dublin today.
The Dún Laoghaire-based senator said she recognised the "enormity" of the task ahead of her if she is to re-organise the party.
She said: "More than any other political organisation our electoral performance was felt like a roller coaster huge highs and deep deep lows. Yet we have had to fight tooth and nail for every first preference vote.
"So yes rebuilding will be a tough task, its a risk, but its a risk worth taking," Ms O'Malley added.
The party's other senator, Ciarán Cannon from Galway East is also expected to formally seek the leadership ahead of the closing date for nominatons tomorrow.
The contest will be decided by an electoral college made up of the parliamentary party (40 percent); local authority members and the national executive (30 percent) and the party's ordinary members (30 percent).
The new leader will be announced on April 16th.