Nelson's leadership came under intense pressure throughout 2008. Newspoll polling in February 2008 set a record low "Preferred Prime Minister" rating for any opposition leader at 9 percent, with March polling setting another record of 7 percent, with two party preferred setting another Newspoll record at 37-63 percent. In response to increased speculation about his leadership Nelson commented in April that he "will keep fighting and standing up for everyday Australians."
Support for Nelson as leader within the Liberal Party had all but collapsed by the end of July 2008, in part due to repeated gaffes on emissions trading and climate change. Expected to challenge him was either Peter Costello or Malcolm Turnbull, upon the release of Costello's book, The Costello Memoirs. Costello stated he would not be making any move for the Liberal leadership, but media outlets capitalised on Costello's failure to categorically rule out any future leadership challenge. Some MPs said he "still remained ready to assume the leadership later in the electoral cycle".