Despite securing the backing of conservative Liberal MPs led by Nick Minchin and Tony Abbott in the last leadership ballot, many conservatives are angered by Opposition Leader Brendan Nelson’s push to introduce federal reform of the party and believe he’s too weak to lead them to victory at the next election.

Those close to Costello are more convinced the former treasurer will remain in politics and take the leadership. Four weeks ago many of them rated the odds of him quitting politics at 80-20 - 80 per cent he would walk away and 20 per cent he would stay. This week they’re putting it at 50-50 and firming.