WASHINGTON — President Barack Obama campaigned on a promise to “reinvigorate” antitrust enforcement. Attorney General Eric Holder Jr. spoke of “ensuring fairness in the marketplace” in his first official remarks. But antitrust lawyers question whether the slumping economy will force the new administration to scale back its ambitions for the Antitrust Division.

Obama has placed his faith in Hogan & Hartson’s Christine Varney, his nominee to head the Justice Department’s Antitrust Division. A former Federal Trade commissioner and an expert in antitrust and Internet law, Varney could end a long-standing rift between the FTC and Justice, usher in a period of stiffer merger review standards, and draw the Justice Department into the fold of fresh theory, antitrust lawyers say. And they expect she’ll build on the muscular cartel enforcement that was a hallmark of the division during the Bush administration.