Jared Leto, best supporting actor winner for his role in "Dallas Buyers Club", speaks on stage at the 86th Academy Awards in Hollywood, California March 2, 2014. [Photo/Agencies]

The Academy Awards kicked off on Sunday by bestowing the best supporting actor Oscar on favorite Jared Leto for his role as a transgender woman in "Dallas Buyers Club," in a night that may yield few surprises apart from the tight best picture race.

Dressed in a tuxedo, returning host Ellen DeGeneres opened the 86th annual Academy Awards taking friendly jabs at nominees, from Jennifer Lawrence for her tripping on the stage last year to Leto. "Boy, is he pretty," she said.

Leto, who returned to acting after a six-year break with the portrayal of Rayon in the low-budget AIDS drama, thanked his mother and honored victims of AIDS.

"This is for the 36 million people out there who have lost the battle to AIDS," Leto said in his acceptance speech.

In one of the strongest years for film in recent memory, the Oscars are expected to be scattered widely among the many acclaimed movies.

But two distinct films have dominated the race for the coveted best picture Oscar, the final award of the night: the slavery drama "12 Years a Slave" is the presumed frontrunner but the space thriller "Gravity" has a strong chance.

Bedecked in gowns, tuxedos and even shorts, the world's top actors and actresses strode down the red carpet right after the sun broke through four days of heavy rain that threatened to put a damper on Hollywood's top honors.

"It has been raining. We're fine. Thank you for your prayers," said DeGeneres in making fun of Los Angeles' aversion to rain.

One of the most notable names on the awards season fashion radar this year, best supporting actress nominee Lupita Nyong'o, wore a blue custom-made Prada.

"It's a blue that reminds me of Nairobi and I wanted to have a little bit of home," said the Kenyan actress who plays the hardworking slave, Patsey, in "12 Years a Slave."

British best actor nominee Chiwetel Ejiofor, who plays the slave Solomon Northup in "12 Years a Slave," showed up in the classic tuxedo, while singer Pharrell Williams wore a Lanvin tux with shorts rather than trousers.