The dollar figures are significant enough to reshape the spending landscape in what had otherwise been framed as a contest of grassroots versus institutional Democratic support. Independent expenditure committees tied to the energy sector have emerged as among the largest outside spenders in the race.

Becerra has served as California Attorney General and previously represented Los Angeles in Congress. Steyer, who spent heavily on climate advocacy and two presidential campaigns, has positioned his candidacy around environmental and economic reform.

The industry investment in Becerra does not, by itself, determine how a candidate governs — but it does establish where the money thinks its interests lie. California's campaign finance disclosure requirements make the spending traceable, and the source industries have direct regulatory stakes in decisions made by statewide officeholders.

PG&E in particular remains under scrutiny from state regulators and the courts following its role in several catastrophic wildfires. Chevron operates one of the largest refineries in the state in Richmond.

The primary is Tuesday. If no candidate clears a majority, the top two vote-getters advance to the general election regardless of party. Watch for final independent expenditure disclosures, which campaigns are required to file in the 90-day pre-election window, to show whether additional energy-sector money moved in the race's final days.