Spider-Man 2 snared arecord $40.5m at the North American box office on Wednesday, beating itspredecessor to claim the biggest opening day ever in movie history.

The first-day U.S.-Canadian haul for Spider-Man 2 passed the previous opening-day record of $39.4million set by the original Spider-Man movie in May of 2002 - all the more impressive since the first filmdebuted on a Friday.

Fuelled by glowing reviews and a built-in fan base generatedfrom the first Spider-Man film, theheavily promoted sequel also shattered the previous record Wednesday opening,set by The Lord of Rings: The Return of the King which opened with $34.5m in December.

Spider-Man 2opened in 4,152 theatres - just 11 short of therecord 4,163 for the Shrek 2 debut in May.

While Spider-Man 2now stands as the opening-day champion, the box-office record for any singleday belongs to Shrek 2, whichgrossed $44.8m on Saturday, May 22.

Heading into the long July 4 weekend, the film is poised toperform strongly. Exhibitor Relations president Paul Dergarabedian toldReuters:m"The potential is there for a $50 million-plus day" thiscoming Saturday, a threshold no film has yet crossed in a single day, he said.