Even when they involve 14-foot tiger sharks preserved in formaldehyde or pictures of Jeff Koons in flagrante delicto, commercial art gallery exhibitions in New York don’t often draw capacity crowds. And they almost never move people to line up along the postindustrial streets of Chelsea on weekday winter mornings as if a sample sale were under way.

But at 9:30 Wednesday morning, with the cold wind raising tears in their eyes, Nick and Elspeth Macdonald from Park Slope, Brooklyn, huddled dutifully in front of the Paula Cooper Gallery along with 20 other people. They were all waiting to get inside to spend a little time with “The Clock,” the widely praised 24-hour film by Christian Marclay that weaves together thousands of snippets from throughout the history of the movies (and, to a lesser extent, television), each clip marking the precise minute, or sometimes the second  with a glimpse of a clock or a watch or a snatch of time-related dialogue  in which the viewers are experiencing it in real time.

Over the last three and a half weeks the exhibition has built itself into an unlikely kind of rock-concert phenomenon, with crowds lined up on West 21st Street as late at 2 a.m. on Saturdays, when the gallery remains open overnight to show the film in its entirety, in a makeshift theater space that seats about 80 people. And as the exhibition approaches its final weekend (it closes on Saturday), the crowds have continued to build. By the gallery’s rough count, more than 780 people passed through on Tuesday alone  some spending only a few minutes, some spending hours  and almost 7,000 people have watched the piece since gallery workers began to keep track on Feb. 4.