Despite those remarks many colleagues still believe the MP will fight and win another preselection battle for the northern beaches seat she has held since 1994. Jim Longley. Credit:George Fetting But it now seems possible she will at the very least be challenged for the seat next year. A successor would inherit the bluest of the blue ribbon Liberal seats in Sydney, with a margin of 15 per cent and a history of long-serving local members, but also a likely swing against the party. Loyalty to Mrs Bishop in local party branches is viewed as the strongest check against a challenge and the decisive factor in a safe seat preselection.

"The branches are pretty solid for her for one more go," said one party insider. Tom Switzer. If Mrs Bishop were to retire that support might benefit of her chief of staff, spokesman and local numbers man Damien Jones, heretofore seen as her probable successor. Journalist and academic Tom Switzer - a former chief of staff to Brendan Nelson who held the neighbouring seat of Bradfield until 2009 - was also scotching suggestions he would run. "My heart's not in it". Senator Concetta Fierravanti-Wells may also get a promotion. Credit:Andrew Meares

Mrs Bishop rose through the ranks with an allegiance to a branch of the party's right faction known as the Uglies. But as the Liberal Right splintered Mrs Bishop became aligned with the party's "centre-right", and factional figures such as Alex Hawke. Other party insiders say Mackellar's local politics is largely free of factional influence, though Mrs Bishop's conservatism is thought to partly explain her popularity. One man who enjoyed local support previously, left faction Liberal and former state party leader John Brogden, now the CEO of Lifeline, is thought to have ruled himself out. NSW Senator Concetta Fierravanti-Wells, who is from the party's right faction, has a local connection too and lives on Mrs Bishop's street.

"I am happy in the Senate," Senator Fierravanti-Wells said on Tuesday. Former Premier Barry O'Farrell reaffirmed that he had "called quits on politics", while parliament gossip that current Premier Mike Baird might challenge is not viewed as credible. Julian Leeser, who works in government relations for the Australian Catholic University, has long been touted as a potential successor to Philip Ruddock's northern Sydney seat of Berowra. Mr Leeser declined to comment. Loading Businessman and right-wing party reformer, Walter Villatora, whose political patch is in the adjacent federal seat did not return calls and may be mooting a run. He and John Ruddick - also said by some to be eyeing the seat - are pushing to drastically change the way party preselections are run with the introduction of plecbiscites.

Former NSW Minister and current senior bureaucrat Jim Longley has been considered a likely challenger in the past but could not be contacted on Tuesday.