Sen. Grassley Concerned About Obama's Expected FBI Chief Nominee

James Comey has connections to the hedge fund Bridgewater Associates

A top Republican senator is expressing concern after sources confirmed to Fox News President Obama is planning to nominate James Comey,  a former Justice Department official under President George W. Bush, to be the next director of the FBI.

Comey, a Republican, would replace current director Robert Mueller, who has led the agency since 2001. His term expires in September.

Iowa Sen. Charles Grassley, the top Republican on the Senate Judiciary Committee, said he had not heard from the White House about Comey's nomination, but that he was concerned about Comey's connections to a Connecticut-based hedge fund Bridgewater Associates.