Melissa Leo won the Academy Award on Sunday for her supporting role in "The Fighter," a movie that propelled the 50-year-old actress into the mainstream for the first time in her career.

Leo was considered a favorite for the prize, but faced strong competition from both co-star Amy Adams and Helena Bonham-Carter for "The King's Speech." All played real-life characters.

Leo starred in "The Fighter" as Alice Ward, the feisty mother of two New England boxing heroes played by Mark Wahlberg and Oscar nominee Christian Bale. While her characterization of the brassy matriarch was not exactly sympathetic, Leo has gone out of her way during awards season to paint Ward as an unsung heroine with a good heart.

It marked Leo's second Oscar nomination after she received a nod two years ago for her lead role in "Frozen River," an arthouse drama that grossed just $2.5 million at the North American box office. "The Fighter," by contrast, has earned about $88 million to date.

The other nominees were Hailee Steinfeld for "True Grit" and Jacki Weaver for "Animal Kingdom."