Thankfully, Jim Carrey‘s embarrassing stint on American Idol wasn’t all in vain.

Horton Hears a Who earned $45 million dollars over the past weekend, trouncing the competition.  Although the kid-friendly flick has had the biggest opening of 2008 so far, the film falls in the middle of the pack when it comes to Dr. Seuss adaptations.  How The Grinch Stole Christmas opened with $55 million back in 2000; A Cat in the Hat took in $38.3 just three years later.

Horton‘s premiere also made a nice statement for non-Pixar related films overall.  This animated movie found itself in fifth place behind other cartoon debuts.  (Disney’s Finding Nemo, Monsters, Inc., Cars and Ratatouille rank one through four.)

The only other new entries in this week’s Top Ten were the mixed-martial arts pic Never Back Down and the post-apocalyptic thriller Doomsday.

1. Horton Hears a Who, 20th Century Fox,  $45,012,998 (avg. $11,384)
2. 10,000 BC, Warner Bros,  $16,773,312 (avg. $4919)
3. Never Back Down, Summit Entertainment,  $8,603,195 (avg. $3153)
4. College Road Trip, Disney,  $7,810,400 (avg. $2886)
5. Vantage Point, Sony,  $5,462,747 (avg. $1979)
6. The Bank Job, Lionsgate,  $5,054,961 (avg. $3134)
7. Doomsday, Universal,  $4,926,565 (avg. $2545)
8. Semi-Pro, New Line,  $3,043,16 (avg. $1341)
9. The Other Boleyn Girl, Sony,  $2,882,846 (avg. $2379)
10. The Spiderwick Chronicles, Paramount,  $2,335,238 (avg. $970)

(You can review last week’s numbers here.)