Katherine O'Regan is now the frontrunner for the seat of Wentworth.Credit:Tamara Dean
It is understood Social Services Minister Paul Fletcher has called key factional players on behalf of Mr Morrison to urge them to back Ms O'Regan.
Ms O'Regan only had an outside chance of winning preselection untilformer Business Council of Australia executive Andrew Bragg pulled out,saying the seat should be contested by a female.
Another leading contender,former ambassador to Israel Dave Sharma,was also struggling to gain enough support because he does not live in the wealthy eastern suburbs electorate.
But it is understood that the moderate faction,which controls Wentworth,will now back Ms O'Regan at the request of the Prime Minister.
NSW Liberals' Women's Council president Mary-Lou Jarvis has the backing of the right faction.
Two other females have also nominated – NSW Liberals'Women's Council president Mary-Lou Jarvis,who has the backing of the right faction,and rheumatologist Maxine Szramka.
The preselection will decidewho contests the October 20 byelection,which was announced on Wednesday. But the decision to effectively discount male candidates has angered some Liberals.