"Juno" started off in larger cities but now has caught fire in smaller towns such as Columbus, Ohio, Wilkes-Barre, Pa., and Cedar Rapids, Iowa, said Peter Rice, Fox Searchlight president.

"The middle of the country has really embraced the movie. And I think the time of year has had a magnifying effect. All the top 10 lists," Rice said. "When the press writes that it's one of the best movies of the year combined with a movie people love, I think those are the defining factors."

Breaking into the top 10 as it expanded to more theaters was Focus Features' tragic romance "Atonement," which came in at No. 10 with $5.1 million.

"Atonement" leads the Golden Globe field with seven nominations, among them best drama and acting honors for Keira Knightley and James McAvoy.

Estimated ticket sales for Friday through Sunday at U.S. and Canadian theaters, according to Media By Numbers LLC. Final figures will be released Monday.

1. "National Treasure: Book of Secrets," $20.2 million.

2. "I Am Legend," $16.4 million.

3. "Juno," $16.2 million.

4. "Alvin and the Chipmunks," $16 million.

5. "One Missed Call," $13.5 million.

6. "Charlie Wilson's War," $8.2 million.

7. "P.S. I Love You," $8 million.

8. "The Water Horse: Legend of the Deep," $6.3 million.

9. "Sweeney Todd: The Demon Barber of Fleet Street," $5.4 million.

10. "Atonement," $5.1 million.