Which organizations officially endorsed Proposition 50 in 2024?

Executive summary — Short answer up front: Multiple Democratic leaders, party organs, and progressive organizations publicly backed Proposition 50 according to the available campaign and party materials: the California Democratic Party and its “Yes on Prop 50” coalition names Governor Gavin Newsom, national Democratic figures such as President Barack Obama, U.S. Senators Alex Padilla and Adam Schiff, Speaker Emerita Nancy Pelosi, and a slate of organizations including Planned Parenthood and the NAACP among endorsers ^{[1] [2]}. Campaign sites and the official voter guide also show a pro-Prop 50 coalition organized under “Yes on 50 / StopElectionRigging.com,” while opponents organized under “Hold Politicians Accountable / VotersFirstAct.org” and “No on Prop. 50—Protect Voters First” ^{[3] [4]}. This summary synthesizes those campaign claims and public coalitions as reported in the provided materials.

1. Who publicly signed on — coalition claims and named endorsers that dominated the record The pro-Prop 50 coalition lists the California Democratic Party as a formal endorsing organization and cites high-profile Democratic figures — Governor Gavin Newsom and nationally prominent Democrats including President Barack Obama, Senators Alex Padilla and Adam Schiff, and Speaker Emerita Nancy Pelosi — as supporters, and frames groups like Planned Parenthood, the NAACP, veterans’ organizations, teachers and nurses’ groups as endorsers ^{[1] [2]}. Campaign-facing materials and the party’s FAQ present this roster as the core endorsement list, and the “Yes on Prop 50” branding appears across pro-Prop 50 communications. Several materials point users to StopElectionRigging.com as the coalition hub for the “Yes” campaign ^{[3] [1]}. These claims come from campaign and party channels and reflect the public face of the pro side rather than an independent audit.

2. Who organized the campaign infrastructure and how the endorsements were presented Campaign materials identify a formal ballot committee — “Yes on 50, The Election Rigging Response Act, Governor Newsom's Ballot Measure Committee” — as a central organizational vehicle and cite the California Democratic Party membership of the coalition ^{[3] [4]}. Independent-expenditure committees and well-funded Democratic-aligned groups are mentioned in reporting about campaign finance, with the “Yes” side reported to have raised significant funds and received major outside support from groups such as House Majority PAC in broader Democratic spending, indicating substantial institutional backing beyond simple endorsements ^[5]. The materials present endorsements as part of a coordinated coalition, linking party authority and leading Democrats to the ballot measure’s messaging and fundraising infrastructure ^[2].

3. What the opposition says and which groups mobilized against Prop 50 Opposition organizers framed their messaging through groups named “Hold Politicians Accountable” and the “No on Prop. 50—Protect Voters First” campaign, with dedicated websites VotersFirstAct.org and counter-campaign materials listed in the official voter information ^{[3] [4]}. These materials do not always present a long roster of traditional civic endorsers the way the pro side’s coalition does; instead the opposition emphasized the sponsorship and funding organization behind the “No” campaign as the identifying credential. Reporting on the broader election context also notes that pro- and anti-Prop 50 camps were built around well-funded committees and outside groups, making endorsements part of a broader contest of resources and messaging rather than isolated organizational statements ^[5].

4. Discrepancies among sources and what they leave out — caution on reading endorsement lists Some sources provide a detailed list of named endorsers (party FAQ and campaign pages), while official voter guides and third‑party reporting sometimes omit exhaustive endorsement lists or focus on committee sponsors instead ^{[1] [3] [6]}. That means the public record as summarized in the available materials is a mix of campaign-compiled endorsement rosters and neutral documents that document committee names and funding but not every organizational signatory. Where campaign pages list groups like the CA Federation of Labor, CA Teachers Association, SEIU CA State Council, and sector-specific associations (veterans, teachers, nurses), those appear as coalition claims rather than independent confirmations within the voter guide summaries ^[1].

5. Bottom line for verification and next steps if you need an audit-quality list The most reliable way to convert these campaign claims into a verified endorsement list is to cross-check the campaign’s published coalitions (StopElectionRigging.com / Yes on 50) against press releases and endorsement pages of each named organization and the California Secretary of State’s committee filings and the official voter guide for formal committee sponsors ^{[3] [5]}. For immediate citation use, the provided materials consistently attribute endorsements to the California Democratic Party, Governor Gavin Newsom, major national Democratic figures named above, Planned Parenthood, the NAACP, and several labor and professional associations as the principal supporters of Proposition 50 ^{[1] [2]}. If you want, I can produce a verified checklist that matches each named endorser to an original press release or endorsement page.