"Iron Man" bolts past $300 million at box office:

LOS ANGELES - "Iron Man" will become the first picture of the year to hit $300 million at the North American box office on Thursday.

Through Tuesday, the Marvel-produced comic book adaptation had rung up an estimated $299.3 million in the United States and Canada. And with recent daily grosses for "Iron Man" of no less than $680,000, there was no question about its blowing past the rarefied $300 million mark Thursday.

Last year produced a trio of $300 million movies, led by "Spider-Man 3" with $336.5 million. It took just 23 days to hit $300 million, while "Iron Man" required 51 days. Still, expectations were not nearly as lofty for the Robert Downey Jr. picture before it opened on May 1.

Last May kick-started two other $300 million grossers: "Shrek the Third" ($322.7 million) and "Pirates of the Caribbean: At World's End" ($309.4 million).

Among summer 2008's other big openers, "Indiana Jones and the Kingdom of the Crystal Skull" had earned $279.5 million through Tuesday. Once considered a lock for the $300 million club, the latest installment in the Steven Spielberg franchise might have to claw its way to that level.