Washington ? A congressman from the New Jersey shore area is asking the U.S. Attorney General to investigate whether the state’s top federal prosecutor is violating the law by running a stealth campaign for governor.

Rep. Frank Pallone, D-Long Branch, N.J., said he was “extremely troubled” that top Republican Party officials are promoting U.S. Attorney Chris Christie as a candidate for governor while Christie continues to serve as the state’s top federal lawman.

He asked Attorney General Michael Mukasey in a letter Friday to provide “guidance and clarification on what the appropriate role for the U.S. Attorney is in political affairs, if any.”

Christie declined to comment through a spokesman. Peter Carr, a spokesman for Mukasey, said the Justice Department would “review the letter and respond appropriately.”