After broad speculation that Internet buzz could turn Fox comedy “Borat” into “Snakes on a Plane 2,” the Sacha Baron Cohen vehicle behaved more like “Fahrenheit 9/11” over the frame, coming in at No. 1 with $26.3 million. Left-field hit won the weekend handily against all odds, playing on just 837 screens. “Borat” drew a whopping per-engagement average of $31,511, as the pic brought in an aud that was almost half over 25 as well as the expected college crowd. Monday morning quarterbacks will wonder whether Fox could have captured even more B.O. dough had the studio rolled out “Borat” more widely. But the studio’s execs say that the movie plays best in a packed house, and that the initial run built the word of mouth that a pic such as this would need to expand. Disney’s “The Santa Clause 3,” the No. 2 finisher, unspooled on 3,458 to hit $20 million. Disney said it had been expecting to finish at somewhere between $19 million and $21 million. “Borat” won the day, in part, because “Clause” and Paramount/DreamWorks Animation’s “Flushed Away” — which washed in at No. 3 with $19.1 million — split the family aud, while the fictional Kazakh TV commentator brought in adults and teens.