Participation in Missouri's delegate selection process is open to all voters who wish to participate as Democrats. Missouri has open primaries, voters may select the Party of their choice at state run polling locations and can change their party affiliation at any time. Voters must be declared Democrats for this party run primary. No person shall participate in the Democratic nominating process who also participates in any other party's process.

Saturday 23 March 2024: Missouri Party-run Primary. Hours 8:00a-12:00p CDT (1300-1700 UTC). Delegate Pledging: Proportional Primary. Voter Eligibility: Open Primary. Write-ins are not allowed. Votes may be cast by postal mail, facsimile, email, or in person.

Party-run Primary (preliminary)
Included in Nationwide vote.

64 of 71 delegates to the Democratic National Convention are pledged to presidential contenders based on the results of the voting in today's Missouri Presidential Primary. 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.

• 42 district delegates are to be allocated proportionally to presidential contenders based on the primary results in each of the State's 8 congressional districts.
• In addition, 22 delegates are to be allocated to presidential contenders based on the primary vote statewide.
  • 14 at-large National Convention delegates
  • 8 Pledged PLEOs

Party-run Primary

Thursday 18 April 2024: Ward, Township, Legislative District, and County Mass Meetings. These meetings elect state level delegates to the Congressional District and State Conventions.

Thursday 9 May 2024: Congressional District Conventions. Hours reportedly begin at 7:30p CDT (0030 UTC).

National Convention District Delegates are elected according to the results of the Primary.

Saturday 18 May 2024: State Committee.

National Convention Pledged PLEO Delegates are elected according to the results of the Primary.

Saturday 22 June 2024: State Convention in Jefferson City.

National Convention At-Large Delegates are elected according to the results of the Primary.

The remaining 7 National Convention delegates consist of

• 7 Unpledged PLEO delegates:
• 4 Democratic National Committee members.
• 2 Members of Congress (0 Senators and 2 Representatives).
• 0 Governors.
• 1 Distinguished Party Leader (former U.S. House Majority Leader Richard Andrew "Dick" Gephardt).

These 7 delegates and will go to the Democratic National Convention officially "Unpledged".

On 29 June 2022, HB 1878, which repeals the Presidential primary, was signed into law by Governor Michael L. "Mike" Parson (Republican). On 24 April 2023, HB 347, HB 267, SB 602, was defeated 65-56. Those bills would have reinstated the presidential primary election. Hence, there is no state run 2024 Presidential Primary in Missouri.

HB 347, HB 267, SB 602 would reinstate the presidential primary election to the 1st Tuesday after the 1st Monday in April (HB 267) or 2nd Tuesday after the 1st Monday in March (SB 602). The bill was defeated 65-56 on 24 April 2023.

12 May 2023: SB 96 would set the Presidential Preference Primary to the 1st Tuesday after the 1st Monday in March.

13 May 2023: The Missouri legislature has adjourned without restoring the Presidential Primary in 2024.