California spent the 2024 cycle drowning its state legislative races in outside money. By the final days of the campaign, independent-expenditure committees — the corporate- and labor-funded groups that spend to support or oppose candidates without coordinating with them — had poured nearly $100 million into Assembly and state Senate contests, including more than $42 million in the final month alone.
That spending is reported to the state's Cal-ACCESS system, the antiquated campaign-finance portal the Secretary of State has been trying to replace since 2021. Because the portal does not expose clean machine-readable data, the figures below are aggregated from filings as analyzed by CalMatters, with broader context from OpenSecrets and the Secretary of State. See methodology for details and caveats.
Independent expenditures in legislative races kept climbing cycle over cycle. Measured from September 1 of each election year through the final days before the election:
| Cycle | Spending since Sept. 1 | Change vs. prior cycle |
|---|---|---|
| 2020 | ~$32 million | baseline |
| 2022 | ~$40 million | +25% |
| 2024 | $51.5 million | +29% |
The $51.5 million figure counts only the post–Labor Day surge; total outside spending across the full cycle approached $100 million.
A single ride-share company was the largest source of outside money in the entire legislative landscape, followed by the oil industry and a labor-backed nurses-and-educators coalition.
| Spender | Reported independent expenditures | Notes |
|---|---|---|
| Uber (PAC) | > $7 million | About 7% of all outside legislative money — the single largest source |
| Coalition to Restore California's Middle Class (oil industry) | > $4.7 million | Funded by Chevron, Valero, Marathon and others; ~$4M came after Sept. 1 |
| Nurses and educators coalition | $2.7 million | Concentrated in a single Senate race (SD 35) |
Much of the money was spent against candidates rather than for them — and in several cases the opposition spending dwarfed what the candidate raised for their own campaign. The starkest example: Laura Richardson faced more than $2.5 million in opposition spending while spending only about $428,000 herself.
| Candidate | Opposition spending | Context |
|---|---|---|
| Laura Richardson (D) | > $2.5 million | State Senate District 35; spent only ~$428,000 on her own campaign |
| Kipp Mueller (D) | ~$2.3 million | Targeted state Senate contest |
| Suzette Martinez Valladares (R) | ~$2 million | Targeted state Senate contest |
On the supporting side, the nurses-and-educators coalition put $2.7 million behind Democrat Michelle Chambers in Senate District 35 — the same race driving the opposition spending against Richardson, a Democrat-versus-Democrat runoff that became one of the cycle's most expensive. In a Los Angeles Assembly race (District 57), Uber spent more than $443,000 backing Democrat Sade Elhawary over fellow Democrat Efren Martinez for an open seat.
Legislative races were not where the biggest money landed in 2024 — California's ten statewide ballot measures pulled in more than $350 million combined (a late-October snapshot). The most expensive fight by far was over rent control: Proposition 33 and the closely related Proposition 34 together drew more than half of all ballot-measure money. Proposition 33 alone topped $100 million:
| Side | Amount raised |
|---|---|
| Support (Renters & Homeowners for Rent Control, Yes on 33) | > $40 million |
| Opposition | $67.2 million |
The figures above cover Proposition 33 only; counted together with the related Proposition 34, the rent-control fight accounted for more than half of all 2024 ballot-measure spending.
Three things stand out. First, the money is increasingly outside money: independent-expenditure committees, not the candidates' own campaigns, now drive the most expensive legislative races, and they grew nearly 30% over 2022. Second, the spending is concentrated — a handful of corporate and labor interests (a ride-share company, the oil industry, public-sector unions) account for an outsized share. Third, some of the most expensive races were Democrat-versus-Democrat runoffs, a direct product of California's top-two primary system, where outside groups effectively pick which Democrat they want by spending millions to tear down the other.
The transparency story underneath all of this matters too. The fact that the cleanest way to understand California's campaign money is through journalists' hand-aggregation of an aging state portal — rather than a usable public data feed — is itself a finding. A replacement for Cal-ACCESS is not expected until after the 2026 statewide election.
Spending figures were aggregated from California Secretary of State Cal-ACCESS filings as reported and analyzed in published sources, not by directly scraping the Cal-ACCESS portal, which does not publish clean machine-readable independent-expenditure data. Dollar amounts are rounded as reported and reflect spending disclosed as of the source publication dates — the legislative figures from a November 4, 2024 analysis and the ballot-measure figures from a late-October 2024 snapshot, both shortly before the November 5 election. These are pre-election snapshots, not final or certified post-election totals; late 24-hour reports and Election Day filings are not captured. Where a figure is approximate it is marked with a tilde (~) or ">". Numbers should be read as best-available estimates from public filings.
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