This Presidential Primary coincides with a state/local primary. These coinciding primaries tend to have an impact upon voter turnout.

Under California law, voters must be registered as Republicans to request a Republicans primary ballot.

Tuesday 5 March 2024: California Primary. Hours 7:00a-8:00p PST (1500-0400 UTC). Delegate Selection: Winner-Take-Most Primary. Voter Eligibility: Closed Primary.

Primary
Source: California Secretary of State.
Status: Official. Retrieved: Thursday 13 June 2024.
Included in Nationwide vote.

All 169 of California's delegates to the Republican National Convention are pledged to presidential contenders in today's California Presidential Primary.

• If a presidential candidate receives a majority (50% plus 1) of the ... statewide vote, that candidate shall be awarded all of California's delegates.... [Article VI. Section 6.01 (A)(2)]
• If no candidate receives a majority of the ... statewide vote, then delegates ... shall be awarded proportionally. Starting with the candidate who received the most votes statewide, compute (candidate's statewide vote) × (total number of at-large delegates) ÷ (total vote statewide) and round up to the next highest integer. Continue with the next highest vote getter until all delegates are assigned. It is not clear if the 3 RNC delegates are included in this category. The presidential candidate's representatives name their delegates.... [Standing Rules and Bylaws of the California Republican Party. Article VI. Section 6.01 (A)(2), (B)(1)]

Primary
Source: California Secretary of State.
Status: Official. Retrieved: Thursday 13 June 2024.

Trump, having received in excees of 50% of the statewide vote, wins all 169 delegates.

3 party leaders, the National Committeeman, the National Committeewoman, and the chairman of the California's Republican Party, will attend the convention as pledged delegates by virtue of their position.

Each delegate to the Republican National Convention shall use his or her best efforts at the convention for the party's presidential nominee candidate from California to whom the delegate has pledged support until the person is nominated for the office of President of the United States by the convention, receives less than 10 percent of the votes for nomination by the convention, releases the delegate from his or her obligation, or until two convention nominating ballots have been taken. Thereafter, each delegate shall be free to vote as he or she chooses.... [California Elections Code Section 6461.(c)]