But who will fill an empty town board seat is still up in the air.
Altadonna is considered a lock to replace Steven Labriola, who resigned in February to become chief of staff for county Comptroller George Maragos, the sources said Wednesday.
Several people are being considered to replace Councilwoman Elizabeth Faughnan, who resigned last month to become deputy executive director of NuHealth System, which runs Nassau University Medical Center in East Meadow.
There is no word when the town board will put a resolution on a meeting agenda to make an appointment for either position. But it's clear appointees will fill the positions. The customary practice is to appoint a replacement who can run as an incumbent in the next regular election.
Altadonna, 53, mayor since 2001, said, "I have no comment."
The sources said the names most discussed to replace Faughnan are Sea Cliff Mayor Bruce Kennedy; Oyster Bay resident Donald MacKenzie, who ran unsuccessfully in a 2011 primary to gain nomination for a county legislature seat; and Lou Imbroto of Plainview, an attorney who ran against Assemb. Charles Lavine (D-Glen Cove) in November.
But one party source said the seat could go to someone not on the list.
The sources said geography will factor heavily in filling the board seat. Faughnan is from Locust Valley. While all six board members run at-large, the GOP has always controlled the town board and always fills one seat with someone from the North Shore.
Kennedy and MacKenzie live north of Route 25A, while Imbroto lives south of it, which could put him at a disadvantage.
Kennedy, 48, mayor of Sea Cliff since 2009, ran as GOP nominee for the county legislature in 2011 under district lines voided by the Court of Appeals. Kennedy said, "I am honored to be considered by the party and Supervisor [John] Venditto for a seat on the Town Council."
Imbroto and MacKenzie could not be reached for comment.