After the historic $495 million sale of postwar and contemporary art at Christie’s, there was considerable curiosity surrounding Phillips’s far more modest one on Thursday evening. Could the third contemporary art auction of the week do well, considering that at Christie’s on Wednesday night, paintings by Jackson Pollock, Roy Lichtenstein and Jean-Michel Basquiat smashed all previous auction records? Although the struggling boutique auction house managed to win pricier materials than in recent seasons, it had only one real star — Warhol’s “Four Marilyns.” The 1962 painting of Marilyn Monroe, times four, sold for $34 million, or $38.2 million with fees. (Its estimated sale price was $35 million to $45 million.) The buyer, Victoria Gelfand, a director at the Gagosian Gallery, beat out three other bidders. While officials at Phillips declined to discuss the story behind the consignment, people familiar with the transaction say Phillips’s owners, the Russian...