If the estimates hold, The Early Show entertainment contributors Laurie Hibberd says it would be the second-biggest February opening ever, behind the $58 million debut of "Hannibal'' in 2001 and just ahead of last year's ``Daredevil'' at $40.3 million.
That's the biggest opening ever for a romantic comedy. "Barbershop 2: Back in Business" came in a distant second with $15.5 million and "Miracle" was third with $14 million.
The overall box office was down, with the top 12 movies grossing $107.8 million, off 13 percent from the same weekend last year.
"50 First Dates'' was a reunion for Sandler and Barrymore, who starred in "The Wedding Singer,'' which opened over Valentine's weekend in 1998.
Sandler's main audience is males in their teens and 20s, who turned out in force, but women made up 57 percent of the crowds on the strength of Barrymore and the movie's romantic theme, distributor Sony reported.
And the Valentine's weekend sealed the deal with audiences.
"Talk about great timing. For a lot of couples, this was their Valentine entertainment,'' said Paul Dergarabedian, president of box-office tracker Exhibitor Relations.
Sandler plays a womanizer smitten by Barrymore, an accident victim who forgets the previous day's memories each morning, forcing Sandler to dream up new ways for the two to meet and fall in love.
Playing in 3,591 theaters, "50 First Dates'' averaged a strong $11,417 a cinema.
With many people off work Monday for President's Day, "50 First Dates'' should come out of the long weekend about halfway to the $100 million level. The movie is positioned to become the first released in 2004 to top that mark.
Though many critics trashed "50 First Dates,'' the movie earned its share of positive press, with some reviewers taken in by the story's sweetness and Sandler and Barrymore's chemistry.
Almost half of the audience was 25 or older, a more mature crowd than normally turns out to see Sandler.
"I think people were excited to see Adam and Drew paired up again,'' said Rory Bruer, Sony head of distribution. ``And I think one thing I would say about Adam, he's just such a likable guy. He's just so accessible to all audiences. People can relate to him.''
In narrow release, the murder thriller ``Highwaymen,'' starring Jim Caviezel, debuted weakly with $203,000 in 111 theaters for an average of $1,829.
Estimated ticket sales for Friday through Sunday at North American theaters, according to Exhibitor Relations Co. Inc. Final figures will be released Tuesday.
- "50 First Dates," $41 million
- "Barbershop 2: Back in Business," $15.6 million
- "Miracle," $14 million
- "The Butterfly Effect," $5.7 million
- "You Got Served," $5.1 million
- "Along Came Polly," $5.08 million
- "Catch That Kid," $4.35 million
- "The Lord of the Rings: The Return of the King," $4.15 million
- "Cold Mountain," $3.7 million
- "Mystic River," $3.55 million