Box-Office Preview: Melissa McCarthy's 'Tammy' Battles 'Transformers 4'

UPDATED: The comedy hopes to continue McCarthy's winning streak despite dismal reviews, while "Transformers: Age of Extinction" is tipped to stay at No. 1; Dinesh D'Souza's "America" goes after conservatives.

One of America's favorite sweethearts — Melissa McCarthy — goes up against holdover Transformers: Age of Extinction at the Fourth of July box office, along with a slew of other films hoping to provide a picnic for all segments of the moviegoing audience.

Still, with no massive tentpole opening (Age of Extinction rolled out last weekend), revenue isn't expected to match last year's holiday frame, when Despicable Me 2 grossed a whopping $143.1 million between Wednesday and Sunday. To date, North American revenue for the summer is already down a steep 15 percent.

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McCarthy's Tammy, marking the feature directorial debut of her husband, Ben Falcone, opens everywhere Wednesday alongside family film Earth to Echo, supernatural horror title Deliver Us From Evil and conservative author and filmmaker Dinesh D'Souza's documentary America.

Age of Extinction is expected to set off the biggest fireworks with a Wednesday-Sunday gross in the $55 million to $60 million range. The movie has already amassed north of $300 million in worldwide ticket sales.

Tammy will easily crush the new offerings with a $45 million to $50 million debut, considering McCarthy and Sandra Bullock's The Heat took in $47.2 million during the same stretch last year after opening the weekend before. Warner Bros. and New Line are being more conservative, predicting $40 million to $45 million.

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The $20 million road-trip comedy is a key test for McCarthy and Falcone as a filmmaking team. The movie is getting dismal notices so far, but even worse reviews didn't hurt McCarthy's Identity Thief. Co-written and produced by the pair, Tammy stars McCarthy as a fed-up burger joint worker who leaves her husband behind for a trip with her grandmother (Susan Sarandon) to Niagara Falls.

Tammy also stars Falcone, Kathy Bates, Dan Aykroyd, Allison Janney, Toni Collette and Sandra Oh.

Screen Gems and producer Jerry Bruckheimer are aiming for a $20 million opening for Deliver Us From Evil, the summer's first studio horror film, about a New York cop (Eric Bana) who teams with a renegade priest (Edgar Ramirez) schooled in exorcisms to eradicate a series of possessions striking New York City. The movie, directed by Scott Derrickson and costing roughly $30 million to produce, is inspired by the book co-written by real-life cop Ralph Sarchie.

Relativity Media hopes to ignite the family market with Earth to Echo, about a tiny alien robot befriended by humans. Disney made the found-footage film, but put it into turnaround last summer. Relativity paid a modest $13 million to acquire the movie and do reshoots.

Earth to Echo should gross $16 million to $19 million over the five-day holiday stretch.

A wild card is conservative author and filmmaker Dinesh D'Souza's documentary America, which expands nationwide after opening in Houston and Atlanta last weekend. America hopes to match the $6.5 million nationwide launch of D'Souza's hit documentary 2016: Obama's America two years ago. That film went on to become the No. 2 political documentary of all time with $33.4 million in ticket sales.

Lionsgate is distributing America, which debunks the narrative that the United States has been a force of evil across the world through a combination of historical re-creations and interviews with some of the country's harshest critics.