Maryland Election Law Section 8-401

      (a)      A special primary election and a special general election may be held at a time other than the date of a regular primary election and a regular general election:

            (1)      to fill a vacancy in the office of Representative in Congress; or

            (2)      to fill a vacancy in the county council if the charter of that county provides for special elections.

      (b)      (1)      Special elections to fill a vacancy in the office of Representative in Congress shall be held at the time specified in Subtitle 7 of this title.

            (2)      Special elections to fill vacancies in a county council shall be held as provided in the county charter.

      (c)      An election to fill a vacancy in the office of United States Senator shall be held concurrently with a regular election as provided in Subtitle 6 of this title.