Online ticket seller Fandango has announced that it generated more than 36% of the $39 million domestic box office  for preview showings of Disney-Marvel’s “Avengers: Infinity War”  on Thursday night.

Fandango said the sales represented the company’s highest opening night percentage for a superhero movie. It noted that more than 2,500 showtimes sold out on Fandango before the film opened, adding that theater owners are continuing to add new showtimes throughout the weekend to meet fan demand.

The $39 million gross was the fourth-highest preview total in history, trailing only “Star Wars: The Force Awakens,” “Star Wars: The Last Jedi,” and “Harry Potter and the Deathly Hallows — Part 2.” Early estimates on Friday showed that “Avengers: Infinity War” was heading for a $225 million opening weekend, the second best of all time behind only “Star Wars: The Force Awakens.”

According to a Fandango moviegoer survey of more than 1,000 “Infinity War” moviegoers, 96% said they were attracted to the film’s “heart and humor”; 74% said the plot’s secrecy was the major factor for them to see the movie on opening weekend; and 73% watched or re-watched previous Marvel movies at home in preparation for “Avengers: Infinity War.”

Avengers: Infinity War” opened Friday  in 4,474 North American sites — the widest release for a Disney title ever and second only to “Despicable Me 3” at 4,529. It had been forecast to open between $225 million and $245 million.

Fandango, a subsidiary of NBCUniversal, recently launched a Fandango VIP+ rewards program. With every Fandango VIP purchase of “Infinity War” tickets, Fandango is offering a complimentary “Infinity War” poster by Kaz Oomori.