New Rose Institute study analyzes delays in California’s vote counts

The Rose Institute of State and Local Government at Claremont McKenna College has released a report analyzing how California’s transition to vote-by-mail elections has contributed to the state’s slow vote counts. The report, titled Democracy Delayed: The Operational and Partisan Impacts of California’s Election Administration System, shows how this transition has affected both ballot-processing times and partisan outcomes.

California’s slow election administration has drawn national attention as some razor-thin races have taken weeks to resolve. For example, a full week after the 2024 Presidential Election, more than 2 million ballots remained uncounted, and the results of seven congressional races were still uncertain.

The state’s transition to all vote-by-mail elections began with the 2016 Voter’s Choice Act (SB 450), which allowed counties to opt in to all-mail elections. In 2021, AB 37 completed the transition, with all counties formally adopting universal vote-by-mail.

This report explores the effects of the transition at the county level through analysis of the California Secretary of State’s Unprocessed Ballot Reports. The results indicate that, following initial delays, counties generally have become more efficient the longer they use the new system, suggesting that institutional learning plays a key role in improving ballot-processing speed. Notably, these findings indicate that slower processing is not inherent to vote-by-mail elections, and that California’s overall efficiency may improve in future cycles as counties continue refining their procedures.

Beyond administrative challenges, the report identifies small but meaningful partisan effects, especially in close contests. Across four recent election cycles, eight US House races experienced a change in the leading candidate as ballots continued to be counted. In most of these cases, an initial Republican lead flipped to a Democratic victory. This can be attributed to a measurable advantage among late-tabulated votes. Democratic candidates in these key races maintained a consistent advantage in ballots tabulated 14 or even 21 days after the election was held.

The report also finds that Democrats won large net margins among cured ballots, which are ballots flagged for signature or submission issues and later corrected by voters. In 2024, cured ballots almost certainly played a decisive role in the razor-thin victories of Democrats Adam Gray (CA-13) and Derek Tran (CA-45).

As national control of Congress becomes increasingly dependent on a handful of tightly contested districts, California’s election administration procedures have taken on heightened political significance. Looking forward, this report suggests that continued institutional learning may improve processing speed while ensuring vote accessibility for millions of voters. However, the notable partisan effects of these laws will ensure that these procedures may remain in the national spotlight in upcoming election cycles.

This report was authored by Rose Institute researcher Keith Maben ’28 with support from Rose Institute Associate Director Shanna Rose, CMC Professor Andrew Sinclair, and Justin Levitt ’06.

About the Rose Institute of State and Local Government
The Rose Institute of State and Local Government was founded at Claremont McKenna College in 1973. A leading resource for information on California state and local governments, the Rose Institute pursues research projects on elections, government institutions, public opinion, and policy. It also maintains extensive state and local demographic, economic, and political databases. For more than 50 years, the Institute has fulfilled its mission to enhance the education of students at CMC, produce high quality research, and promote public understanding on issues of state and local government, politics, and policy, with an emphasis on California. For more information, visit https://roseinstitute.cmc.edu/.

About Claremont McKenna College
Claremont McKenna College is a private, 1,300-student residential liberal arts college located east of Los Angeles in Southern California. Since 1946, the College’s mission has been to prepare students for thoughtful and productive lives and responsible leadership in business, government, and the professions. Renowned for its Open Academy commitments to freedom of expression, viewpoint diversity, and constructive dialogue, as well as expertise in economics and government, Claremont McKenna also features an accomplished faculty of scholars and committed teachers in the humanities, sciences, and social sciences. Students are drawn to the College’s unparalleled offerings, including: 11 research institutes and centers; the ability to conduct research one-on-one with faculty; and access to leaders, artists, and visionaries who engage with students at the Marian Miner Cook Athenaeum. Claremont McKenna is a member of The Claremont Colleges. For more information, visit cmc.edu.