Hendricks, best known for her roles in the AMC series Mad Men, as well as roles in Drive and Detachment, will compete with model and actress McCarthy, a former Playmate of the Year whose movie career includes roles in Scary Movie and John Tucker Must Die.

They are favourites to portray the late Playboy star’s rise to fame and fall into alcoholism and addiction, which eventually took her life in 2007 at the age of 39, before becoming an iconic figure in modelling circles.

James Cromwell, 72, is rumoured to be close to signing up to play Anna Nicole’s “sugar daddy” – Texan billionaire J Howard Marshall.

Friends of the late star hope that the biopic, which is due to start shooting before Christmas, will reflect her more “sensitive” side when focusing on her troubled son Daniel Wayne Smith, who died aged 20 from a drug-related heart attack six months before an overdose killed Smith in a Florida hotel room.

Actress Isabella Rapone said: “She was anything but the gold-digger many people perceived her as.

“She worshipped the ground her son walked on. I think if he hadn’t died so young, Anna Nicole might well be alive today.”