LOS ANGELES -- A Republican media advisor found dead in the home of actress Carrie Fisher died from an overdose of cocaine and the painkiller oxycodone, the Los Angeles County coroner's office reported.

Robert Gregory Stevens, 42, was found dead Feb. 26 in a guest room of Fisher's Coldwater Canyon home.

They were reportedly long-time friends.

Stevens had a pre-existing heart condition, and the coroner's office determined his death was "accidental."

Earlier, a coroner's official said Stevens also had a reported history of drug abuse.

Fisher, the daughter of Debbie Reynolds and singer Eddie Fisher, chronicled her own history of drug abuse in her book, "Postcards from the Edge," which became a movie starring Meryl Streep.

Stevens served as co-chairman of the entertainment task force for the Bush/Cheney 2004 campaign. He ewas a San Clemente native and an associate with the Washington lobbying group Barbour Griffith and Rogers, where he specialized in foreign campaign consulting. The USC graduate also acted as a liaison between Republicans and the entertainment industry.