Having marched through Hollywood's major guild awards with hardly a misstep, royal film "The King's Speech" has in past weeks been a frontrunner to sweep through the Oscars, but that may be about to change.

With only about 10 days to go before the world's top film honors, Oscar pundits are re-thinking their picks, and as much as co-hosts James Franco and Anne Hathaway are expected to bring a youthful glow to the awards show, the races for best actor and actress could offer some surprises, experts say.

The Academy Awards, where A-list movie stars like Nicole Kidman and Javier Bardem will turn out in their finest gowns, jewelry and tuxedos, unrolls its red carpet on February 27, and already Hollywood is gearing up with a week of celebrations leading up to its biggest night of the year.

But the really big show will be Sunday's awards, where the tension is building not so much over whether "King's Speech" will win best film, as expected. Rather, the question is: can it sweep through the other top categories?.

"It looks like a 'King's Speech' coronation. The question is how wide will its influence spread", said veteran Oscar watcher Tom O'Neil of awards websites goldderby.com and theenvelope.com.

Drama "The King's Speech," which tells how British King George VI overcame his stammer to rally his countrymen on the eve of World War II, is widely expected to win best film after picking up similar awards from Hollywood guilds representing actors, directors, writers and producers.

Among 10 nominees for best movie, "King's Speech" faces its toughest competition from Facebook film "The Social Network," which won top honors among many critics groups but has fallen off the pace in recent weeks.

Other top nominees include ballet drama "Black Swan," "The Fighter," "True Grit" and "The Kids Are All Right."

TIGHT RACES IN ACTING

The tight races for the Academy of Motion Picture Arts and Sciences' Oscars are in acting categories, and perhaps the toughest competition is for best director among "King's Speech" maker Tom Hooper and "Social Network" helmsman David Fincher.

In the best actor race, Colin Firth is widely picked to win for his performance as King George VI, but among actresses, the competition is too close to call between "Black Swan" actress Natalie Portman and Annette Bening in "Kids Are All Right."

Portman turned in a strong performance as a ballerina growing into womanhood, and has claimed many early awards, including Golden Globe and Screen Actors Guild trophies.

But Bening, who portrays a lesbian mother in "Kids," is a three-time loser at the Oscars, and there is a feeling that it is her time to win. Moreover, she is a member of the Academy's Board of Governors and is well-liked in the group.

"Annette Bening has been doing a lot of campaigning, and she has a lot of support," said Pete Hammond, Oscar watcher for Deadline Hollywood. "That (race) is ripe for a slight upset."

Among supporting actors and actresses, Christian Bale playing a drug-addicted boxer in "The Fighter" and Melissa Leo as his mother, are widely-picked to win.