The 20th Century Fox movie, which lampooned last year's epic blockbuster "300," took in an estimated $18.7 million in its weekend debut. It edged out "Rambo," a Lionsgate release starring and directed by Sylvester Stallone, which took in $18.2 million.

"This was a very tight race for the No. 1 spot," said Paul Dergarabedian, president of box office tracker, Media By Numbers, LLC. "I think we tend to underestimate films like 'Meet the Spartans.' Fox has really locked onto something that's extremely popular. "

"Spartans" tells the tale of hero Leonidas who leads a group of 13 Spartans to defend against the invading Persians — including Rocky Balboa, Paris Hilton and other pop culture icons. It was directed by Jason Friedberg and Aaron Seltzer, who produced the parodies "Epic Movie" and "Date Movie."

"Spartans" was popular among teenagers and young adults, who made up about 75 percent of the audience. The film was rated PG-13, while R-rated "Rambo" was popular with older men.

"We are thrilled with the numbers," said Bert Livingston, senior vice president of distribution at Fox. "We made it for young people and they came."

Harvey Weinstein, co-chairman of the Weinstein Co., which co-distributed "Rambo," said he expected the film's mature audience to sustain its popularity at the box office.

"I think we'll have a great hold," Weinstein said.

"Rambo" is the fourth installment of the trademark franchise and stars Stallone as the eponymous Vietnam vet spending his retirement in Thailand when a group of missionaries enlist his help in aiding a village endangered by civil war in Myanmar.

The top 12 movies raked in $117.8 million, up 32 percent from the same weekend last year, when Fox's "Epic Movie" led the box office with $18.6 million.

Last weekend's monster hit, "Cloverfield," which set a January opening record with $41 million, was down steeply at No. 4 with $12.7 million, a 68 percent decline. "27 Dresses," starring Katherine Heigl as the perpetual bridesmaid was third with $13.6 million, and the new thriller "Untraceable," featuring Diane Lane as an FBI cybercrime investigator, rounded out the top five.

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. "Meet the Spartans," $18.7 million

2. "Rambo," $18.2 million

3. "27 Dresses," $13.6 million

4. "Cloverfield," $12.7 million

5. "Untraceable," $11.2 million

6. "Juno," $10.3 million

7. "The Bucket List," $10.2 million

8. "There Will be Blood," $4.9 million

9. "National Treasure: Book of Secrets," $4.7 million