As the State Senate is evenly divided between Democrats and Republicans, New Jersey has two Senate Presidents: Senator John O. Bennett (R) and Senator Richard J. Codey (D). Upon the occasion of Governor James McGreevey travelling outside of New Jersey, the role of Acting Governor has alternated between the two Senate Presidents.

If a Governor-elect fails to qualify within six months of the beginning of the term of office, if a Governor (or Acting Governor) is out of the state continuously for six months, or is unable to perform the duties of the State Supreme Court can decide the Office of Governor vacant. The Legislature must charge the reasons for the vacancy by a two-thirds vote of both houses. The State Supreme court then holds a hearing.

If the Office of Governor is declared vacant, if a governor is removed from office, or if a governor resigns then the Senate President becomes Acting Governor. Again, the Acting Governor remains Senate President. If the Senate President is unable to serve as Acting Governor, then the Speaker of the General Assembly become Acting Governor. An election to choose a Governor will be held the following November.