Despite holding two of the safest seats in NSW, chances are Noreen Hay and Lylea McMahon will face their toughest battles to retain their seats prior to March 2011.A quick-fire ALP preselection process for the seats of Kiama, Heathcote and Keira saw Matt Brown, Paul McLeay and former David Campbell staffer Ryan Park elected unopposed as candidates.However, word is yet to filter out of when nominations will open for Wollongong and Shellharbour, which Labor hold with margins of 26.9 per cent and 21.6 per cent respectively.While there is speculation the party's Left faction is seeking candidates to oppose Ms Hay and Ms McMahon, both are expected to win a rank-and-file ballot should they be challenged.The controversial N40 rule - which allows head office to overrule local preselectors - is still in play for existing and aspiring politicians, particularly in light of Premier Kristina Keneally's plea to ALP head office to call for "new blood" in her party.In Shellharbour, previously known as Illawarra, a rank-and-file ballot hasn't been held since 1993 when Ms Hay, then a left-wing candidate, lost to incumbent MP Terry Rumble.Both Ms Hay and Ms McMahon told the Mercury they supported rank-and-file preselection."It is a decision for head office and I haven't heard anything yet," Ms McMahon said of the timing.Ms Hay said she didn't think it was unusually late. "My first preselection was in 2002 in November," Ms Hay said.In 2006 Ms McMahon benefited from the N40 rule when she was a surprise choice to replace retiring Marianne Saliba. Ms Saliba twice benefited from the N40 rule.Last year it was reported powerbroker Eddie Obeid wanted Ms Hay to move to the upper house so Eric Roozendaal could run for the seat of Wollongong, while weekend reports suggested Labor's head office wanted to find Transport Minister John Robertson, who is in the Legislative Council, a lower house seat before the end of the year.