What started as a close and unpredictable race to box office supremacy wound up an easy win for Nicolas Cage’s latest sci-fi flick, "Knowing," which grossed $24.8 million this weekend, trumping challenges from the hearty laugher "I Love You, Man" and the Julia Roberts-Clive Owen rom-thrill "Duplicity." While I’m somewhat surprised by the outcome — “Knowing” fared much better than I, or most other box office prognosticators, expected — in the end the battle wasn’t even very close. Cage scored his third consecutive No.