Maryland Election Law Section 8-202

      (a)      A principal political party, as determined by the statement of registration issued by the State Board under § 3-509(b) of this article:

            (1)      shall use the primary election to:

                  (i)      nominate its candidates for public office; and

                  (ii)      elect all members of the local central committees of the political party; and

            (2)      may use the primary election in the year of a presidential election to elect delegates to a national presidential nominating convention.

      (b)      Except for a nominee for President or Vice President, the name of a nominee of a principal political party may not appear on the ballot in a general election if the individual has not:

            (1)      been nominated in the primary election; or

            (2)      been designated to fill a vacancy in nomination in accordance with Subtitle 5 of this title.

      (c)      If a political party chooses to permit voters not affiliated with the party to vote in the party's primary election, the chairman of the party's State central committee shall so notify the State Board at least 6 months before the date of the primary election.