B.O. observers are predicting a healthy upswing at the weekend’s domestic B.O., with four new wide releases all likely to amass double-digit tallies.

Sony’s Brad Pitt sports pic “Moneyball” — in a bow that almost directly mirrors the studio’s rollout of “The Social Network” last fall — could attract enough adult moviegoers to win the weekend. But a pair of family-targeted films, Warner Bros.’ “Dolphin Tale” and Disney’s 3D holdover “The Lion King,” are expected to make it a tight three-way race in the $18 million-$20 million range.

If “Moneyball” and “Dolphin Tale” wind up close on Friday, B.O. pundits say “Dolphin Tale” — boosted by 2,700 3D locations — will likely win the weekend since family pics play better on Saturday and Sunday.

The frame’s remaining wide releases, including Lionsgate’s Taylor Lautner actioner “Abduction” and “Killer Elite,” the inaugural release from Open Road Films, are projected to do solid business as well, north of $10 million.

Whether it’s audience malaise or a reflection of product quality, U.S. moviegoers haven’t lately embraced more than two new titles in the market concurrently. Last weekend, for instance, “The Lion King” and “Drive” were the only pics to bow in double digits. (“Contagion” collected $14.5 million in its second frame.)

Bizzers were optimistic that this weekend could see more than two films score double-digit grosses.

Overseas, Sony’s “The Smurfs” could remain on top for a seventh straight week. Last week, the live-action/toon hybrid surged 23% vs. the previous frame thanks to bows in Australia and Italy. But with no new markets, “Smurfs” could feasibly concede this weekend to newer entries like “Abduction,” which launches day and date in 20 territories, including Oz, Brazil and Russia.

“Killer Elite,” too, is bowing simultaneously in the U.S. and several overseas territories, such as Russia and the U.K., via local distribs.

Both “Killer Elite” and “Moneyball” should appeal to primarily over-25 male auds; the latter also could draw plenty of females. “Abduction” has a strong hold on “Twilight” girl fans and should be helped by a less-restrictive PG-13 rating.

Meanwhile, families could be torn between “Dolphin Tale,” which also has support from faith-based auds, and “The Lion King.” But family turnout depends on how the latter plays to adults (“Lion King” drew much better-than-expected support from over-25 auds during opening weekend).

Though “Lion King” has been performing well midweek — a usual boon time for adult auds — the re-released toon still could see a minimal drop in its second weekend, when families typically visit plexes. Some bizzers suggest the film may have seen the bulk of its B.O. draw in its first frame.

Sony is de-emphasizing the opening weekend’s impact to the overall prospects for “Moneyball.” As with “The Social Network,” which opened to $22 million and cumed almost $97 million domestically, the studio anticipates that “Moneyball,” budgeted at a reported $50 million, will develop similar legs, based on strong reviews coming out of the Toronto Film Festival.

In limited release, Roadside Attractions’ docu “Thunder Soul” bows at 35 locations, while Relativity Media’s Gerard Butler starrer “Machine Gun Preacher” opens at four locations in New York and L.A.

Sundance Selects, sister division of IFC Films, launches gay-themed drama “Weekend” at one location. Pic won raves at SXSW and Outfest Film Fests.