Outgoing Taoiseach Brian Cowen said he accepted responsibility for decisions taken in government.
"It's a difficult day for the party," he said.
"I have taken full responsibility and have always taken full responsibility, and I never quibbled or suggested otherwise."
He added: "I am very sorry that there are many good people who will not be part of the Dail."
Fianna Fail leader Micheal Martin said he believed that Fine Gael had managed to secure support from floating voters.
"There's a soft vote there for Fine Gael and Labour, just as there was for us for years," he said.
"I tend to be optimistic by nature so I look at this as an opportunity as well."