HOLLYWOOD, May 12, 2018 (News Wires) - "Avengers: Infinity War" is showing plenty of staying power in North America as it heads for the fourth-highest grossing third weekend of all time at $55 million to $60 million, early estimates showed on Saturday. A pair of new counterprogramming titles were in a battle for second place with Melissa McCarthy's comedy "Life of the Party" tracking for about $18 million at 3,656 sites, followed by Gabrielle Union's thriller "Breaking In" at around $14 million at 2,537 venues. "Avengers: Infinity War" set the all-time record for biggest domestic opening weekend with $257.7 million, then fell 56% to $114.8 million. A similar decline will give the superhero tentpole $56 million to $60 million this weekend. Only "Star Wars: The Force Awakens" ($90.2 million), "Avatar" ($68.5 million), and "Black Panther" ($66.3 million) finished above that mark in their third frames. Early estimates showed "Avengers: Infinity War" with about $16 million on Friday, its 15th day in theaters after grossing $486 million in its first two weeks. It should wind up the weekend at about $545 million — eighth on the all-time domestic list, ahead of "The Dark Knight" at $534.9 million. "Life of the Party" was heading for about $5 million on Friday, including $700,000 from Thursday night previews. Released by Warner Bros.' New Line division, the PG-13 title is aimed at getting mothers and daughters to hit theaters during the Mother's Day weekend. McCarthy plays a mom who joins her daughter (Molly Gordon) in college after getting divorced. McCarthy's spouse, Ben Falcone, directed from a script he co-wrote with McCarthy. "Breaking In," directed by James McTeigue, had been pegged for a bow in the $14 million to $17 million range. Union portrays a single mom who has to protect her two children (played by Seth Carr and Ajiona Alexus) after her father's Malibu mansion is invaded by burglars. Neither new film carries much critical support, with "Life of the Party" rated at 39% on Rotten Tomatoes and "Breaking In" at 30%. The second weekend of Lionsgate-Pantelion's comedy "Overboard" was heading for fourth place with about $8 million, followed by Paramount's sixth weekend of horror hit "A Quiet Place" with $6 million. "A Quiet Place" will wind up the weekend with nearly $170 million domestically. Thanks largely to "Black Panther" and "Avengers: Infinity War," the overall domestic box office is up 4% to $4.16 billion as of May 9, according to comScore. Business is likely to boom in coming weeks with Fox's "Deadpool 2" launching on May 18 and Disney's "Solo: A Star Wars Story" opening on May 25. "We could be looking at a record-breaking May with that triumvirate of huge titles," said Paul Dergarabedian, senior media analyst with comScore. "For moviegoers, this is a perfect month to start the summer. Hopefully, the marketplace will expand over Memorial Day weekend to accommodate these big films."