Disney’s $250 million “John Carter” is off to a rocky start at the domestic B.O., with the 3D fantasy epic tracking for a $28 million to $32 million weekend. Universal’s “The Lorax” should emerge victorious with roughly $40 million, according to estimates based on early Friday returns.For months, Hollywood has speculated that the big-budget “Carter” was a bust — and while the sci-fi pic is fairing “slightly better than expected,” per analysts, the studio appears to be light years away from turning a profit. Based on author Edward Rice Burroughs’ 100-year-old material and having no major stars, “John Carter” has been a challenging pic to market for the Mouse House. Last May, the studio changed the title of the pic from “John Carter of Mars” to simply “John Carter” to distance the pic from paltry performer “Mars Needs Moms,” which turned into a $100 million-plus write-off for Disney last year. “Carter,” directed by Pixar vet Andrew Stanton (“Finding Nemo,” “Wall-E”), stars Taylor Kitsch and tells the story of a Civil War vet who is transplanted to Mars, where he finds himself in the middle of an inter-species war. The New York Times called the film “Messy and chaotic … but also colorful and kind of fun” and a 50% fresh rating on Rotten Tomatoes suggest other critics are just as mixed. Overseas, the pic premiered to an impressive $6.5 million in 3D-happy Russia, but other territories could pose a greater challenge. Meanwhile, U’s “Lorax” is holding very well, with the Dr. Seuss pic only dropping 41% week-to-week, putting the $70 million Illumination Entertainment toon on par to eclipse “John Carter” as the #1 pic domestically. Other new releases, Par’s Eddie Murphy-starrer “A Thousand Words” and Open Road’s “Silent House” are tracking just under $7 million for the frame.