He will be challenged for the spot by former federal MP Peter Hendy, who is pitching himself as a non-aligned “compromise candidate”, Woollahra council deputy mayor and former party state director Richard Shields, and Sydney surgeon Michael Feneley, the director of cardiology at St Vincent’s Hospital.
Sutherland Shire councillor Kent Johns, who has twice been thwarted in his attempts to win preselection for the federal seat of Hughes, is also considering entering the race before nominations close next Tuesday.
Prominent Indigenous leader Warren Mundine, who lost his attempt to hold the southern NSW federal seat of Gilmore for the Liberals in May, is also considering whether he will contest.
But some moderates believe they should not run a candidate against Mr Molan because the winner of the two-year position will be up for renewal in 2022, at the same time as the moderate-aligned Foreign Affairs Minister Marise Payne and conservative Concetta Fierravanti-Wells.
Mr Molan has pledged to stay on in parliament only until the next election, when Senator Sinodinos’ term was due to expire.
Liberal Party members are prevented from speaking to the media during the preselection contests. But a senior Liberal source questioned whether Mr Molan would be prepared to bow out after two years.
Prime Minister Scott Morrison will provide Mr Molan with a written reference to be sent to pre-selectors but will not invest himself in the contest to the degree he did with Sarah Henderson in the recent Victorian Senate preselection.
Catholic Schools NSW boss Dallas McInerney was flagged as a potential candidate last month but has withdrawn and will potentially wait until the next election.
Senator Sinodinos, a former chief of staff to John Howard who will become Australia’s next ambassador to the US early next year, wrote to Liberal NSW director Chris Stone on Friday announcing his departure so the preselection process to replace him could begin.
About 800 delegates who will determine the outcome will vote on his replacement on November 10.