Best actor

Leonardo DiCaprio

“Blood Diamond”

The former child actor picks up his third Oscar nomination as a South African diamond mercenary. The 32-year-old DiCaprio received his first Academy Award nomination as a teenager, for supporting actor for 1993’s “What’s Eating Gilbert Grape.” Two years ago, he earned a best actor nomination as eccentric billionaire Howard Hughes in Martin Scorsese’s “The Aviator.” He was nominated for a Golden Globe for the performance.

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Ryan Gosling

“Half Nelson”

The former Mickey Mouse Club regular earns his first Oscar nomination for his portrayal of a troubled inner city junior high teacher who is befriended by one of his students. Gosling, 26, recently won best actor honors at the Stockholm Film Festival and is nominated for a Screen Actors Guild award as well as a Spirit Award. The National Board of Review of Motion Pictures also awarded him honors for best breakout performance by a male actor. He has joked that he’s extremely proud of his nomination for best kiss by the MTV Movie Awards for the romantic tear-jerker 2004’s “The Notebook.”

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Peter O’Toole

“Venus”

The 74-year-old actor has always been Oscar’s bridesmaid, but never the bride. The Irish-born O’Toole receives his eighth best actor nomination for his poignant performance as aging actor who finds himself attracted to a teenage free spirit. O’Toole holds the record for the most Oscar nominations by a performer without winning, although he did receive an honorary Oscar four years ago. Nominated for a Golden Globe he is also up for a SAG award.

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Will Smith

“The Pursuit of Happyness”

The multiple-Grammy Award winning hip-hop singer who came to fame in the early ‘90s on the TV sitcom “The Fresh Prince of Bel-Air,” Smith receives his second Academy Award nomination in this category for his performance as a single dad struggling to make a better life for himself and his young son, played by Smith’s son Jaden. Smith, 38, who was nominated for best actor for 2001’s “Ali,” was nominated for a Golden Globe for “Pursuit” and is in contention for a SAG award.

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Forest Whitaker

“The Last King of Scotland”

The 45-year-old Whitaker earns his first Oscar nomination for his towering turn as infamous Ugandan dictator Idi Amin. Whitaker, who made his film debut in 1982’s “Fast Times at Ridgemont High” -- the same year he graduated from USC -- has won practically every critical accolade for his performance as well as the Golden Globe. Whitaker is also nominated for a SAG award.