Influential Liberal Tony Abbott has admitted to losing hope over the coalition's poor polling performance under embattled Opposition Leader Brendan Nelson.
He denied he is leading the push for a leadership shake-up in the party, saying Dr Nelson has to be given a fair go.
Mr Abbott earlier remarked that Peter Costello's departure from politics has deprived the Liberals of a great leader, but said the Liberals would be in trouble no matter who was heading the party.
"I've had a lot of conversations with Peter since the election and I think it's a bit of a tragedy that Peter has never been prime minister, probably will never be prime minister.
"But political life is full of might-have-beens."
Former Treasurer Mr Costello has not yet ruled out a comeback to politics to contest the Liberal leadership.