By Allan Lengel

Timothy Murphy, the FBI’s number three person, will fill in for John Pistole, the number two person, and is a likely candidate to take over that spot permanently, sources familiar with the situation tell ticklethewire.com.

Pistole will be leaving the FBI to head up the the Transportation Security Administration.  The U.S. Senate confirmed his presidential appointment on Friday.

Michael P. Kortan, the chief FBI spokesman, declined on Saturday to comment or speculate on the matter.

In 2008, Murphy rose to the number three spot — Associate Deputy Director in charge of FBI personnel, budget, administration and infrastructure. He was previously assistant Director of the FBI’s Finance Division.

He began his FBI career in 1988 Murphy. He served in four field offices, including Newark, Tampa, Washington and Cincinnati , where he worked cases in a variety of areas including counterterrorism, organized crime and drugs and as a pilot in the aviation program.

In the Washington field office, he worked an assistant special agent in charge and he served as a special agent in charge in Cincinnati.

At headquarters, some of his posts included supervisory special agent in the Executive Development and Selection Program, unit chief of the Senior Executive Service Unit, unit chief of the Director’s Research Group and special assistant to FBI Director Robert S. Mueller III, according to an FBI bio.