Warner Bros.' The Dark Knight is taking aim at another box-office record, hoping to reach $300 million in domestic ticket sales faster than any other film. Today's (Friday) Daily Variety observed that the movie "has a real shot" at doing so by the end of the weekend, thereby hitting the $300-million mark in 10 days. The current record is held by last year's Pirates of the Caribbean: Dead Man's Chest , which reached $300 million in 16 days. Star Wars -- Episode III: Revenge of the Sith did it in 17 days and Spider-Man 3 in 19. The chances of The Dark Knight remaining a superforce at the box office this weekend appear to be enhanced by mediocre tracking for the films that are making their debut this weekend, including the new X-Files sequel and the comedy, Step Brothers . "Everyone's playing for No. 2 this weekend," Sony marketing chief Jeff Blake told the Los Angeles Times. Moreover, some analysts have noted that a large percentage of moviegoers who bought tickets for the Batman film earlier in the week were return customers. The film grossed a phenomenal $24.5 million on Monday, $20.9 million on Tuesday and $18.4 million on Wednesday, to bring its total gross on Wednesday to $222.1 million. Assuming that the film earned $15-18 million on Thursday, it would need only to do about 40 percent percent of the business it did last weekend between today and Sunday to hit $300 million in 10 days.