Participation in Maine's delegate selection process is open to all registered voters who at least 18 years old on the general election date and are enrolled in the Democratic Party. Residents who are enrolled in another party must change their affiliation at least 15 days before the primary. A resident who is unregistered or not enrolled in any party may register to vote on the day of the primary.

Tuesday 5 March 2024 (presumably): Maine Primary. Hours reportedly 6:00a-8:00p EST (1100-0100 UTC). Voting places open between 6:00a Eastern Time and 10:00a Eastern Time depending on the size of the town. Delegate Pledging: Proportional Primary. Voter Eligibility: Closed Primary.

Primary (preliminary)
Included in Nationwide vote.

24 of 33 delegates to the Democratic National Convention are allocated to presidential contenders according to the results of the primary. The party will use the actual vote, rather than ranked-choice voting, to allocate its delegates. A mandatory 15 percent threshold is required in order for a presidential contender to be allocated National Convention delegates at either the congressional district or statewide level. How the Democratic Proportional Delegate Allocation Math works.

• 16 district delegates are to be allocated proportionally based on the presidential preferences expressed in each of the State's 2 congressional districts.
• In addition, 8 delegates are to be allocated to presidential contenders based the support for the presidential contenders in the state as a whole.
• 5 at-large National Convention delegates
• 3 Pledged PLEOs

Primary (preliminary)

Sunday 10 March 2024 (presumably): Maine Municipal Caucuses.

The Municipal Caucuses meet to choose delegates to the State Convention. Those State Convention delegates will be pledged to presidential contenders according to results of their respective caucuses, and not the results of the Presidential Primary.

Saturday 25 May 2024 (presumably): State Convention.

National Convention delegates are elected at the state Convention according to the results of the Primary.

The remaining 9 National Convention delegates consist of

• 9 Unpledged PLEO delegates:
• 4 Democratic National Committee members.
• 3 Members of Congress (1 Senator and 2 Representatives).
• 1 Governor.
• 1 Distinguished Party Leader (former Senate Majority Leader George Mitchell).

These 9 delegates and will go to the Democratic National Convention officially "Unpledged".

25 March 2020: The unpledged delegates are: Gov. Janet Mills, Reps Chellie Pingree and Jared Golden, and former Senate Majority Leader George Mitchell, MDP Chair Kathleen Marra, Vice Chair Erik Gundersen, and DNC members state Rep. Diane Denk and state Sen. Troy Jackson.