1964 New Jersey Democratic presidential primary

The 1964 New Jersey Democratic presidential primary was held on April 21, 1964, in New Jersey as one of the Democratic Party's statewide nomination contests ahead of the 1964 United States presidential election.

In the binding delegate primary, competing slates of uncommitted delegates contested the election on a ballot The New York Times called "one of the most confusing in the state's recent history."^[1] In most districts, however, the "Regular Democratic Organization" slate assembled by state and local party leaders ultimately ran unopposed.

In the preference primary held at the same time, no candidate filed to run,^[1] but President Johnson easily received a large majority of write-in votes, though fewer than six thousand were cast.^[2] In some counties, a write-in vote was difficult or impossible to cast due to the nature of the voting machines used, and no vote was recorded in Cape May or Essex counties.

Thirty-five delegates were elected at-large on a statewide ticket, and another three were elected from each of the state's 15 congressional districts.^[2]

On March 9, the legislature passed an act authorizing voters to vote for delegates as a bloc, if they chose to be grouped together, if a county clerk found that the capacity of voting machines made it impossible to vote for individual delegates. Nine counties (Atlantic, Bergen, Burlington, Camden, Hudson, Middlesex, Monmouth, Ocean, and Somerset) opted for this system, but on April 2, Superior Court judge Nelson K. Mintz ruled that adapters for voting machines used in the state were available and that the county clerks could not "substitute their standard for the standard of 'impossibility' prescribed by the Legislature".^[3]

At the 1964 Democratic National Convention in Atlantic City, the New Jersey delegates joined a voice vote nominating Lyndon B. Johnson for election to a full term.