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Ballot Explained

U.S. House · November 3, 2026

Who's running in California's 10th congressional district

2 candidates are on the ballot. Below is what each one says they stand for, what they have actually done in office or in public life, and the arguments published for and against them — each quoted from a named source rather than summarised by us.

Candidates
2
Incumbent
Mark DeSaulnier
Parties
Democratic · Republican
State primary
Jun 2

Candidates appear in ballot order. We do not rank them, score them, or recommend one — here is how this is put together, and here is what the office actually does.

2 candidates · ballot order · Mark DeSaulnier currently holds this seat

Medium confidenceMedium confidenceThe candidate's stated positions and basic record are documented, but coverage is thin — often little independent reporting, or criticism from only one side.What would raise it: More independent reporting, a documented voting record, or published criticism from a named opponent would raise this.

What they say they stand for

Their own words. Claims, not verified facts.

  • Growing the economy and lowering inflation.
  • Cutting health care costs and expanding access to care, including protecting medical research funding.
  • Expanding affordable housing and lowering housing and transport costs for working families.
  • Protecting Medicare and Social Security.
  • Protecting air quality standards and advancing the transition to clean energy.
  • Protecting reproductive freedom.
  • Ensuring workers have a voice as automation reshapes the economy.

What they’ve actually done

Documented record from official sources.

  • U.S. Representative since January 2015; has held the 10th District seat since 2023 and the 11th District before that.
  • California State Senator from 2008; member of the State Assembly from 2006.
  • Contra Costa County supervisor and Concord city councilmember before that.
  • Worked as a probation officer, truck driver, hotel services employee and small business owner.
  • Led the June 2, 2026 primary field.

Arguments in favor

  • He is ranking Democrat on the House Ethics Committee, and his own legislative work is unglamorous district business: guardrail safety on federal highways and accountability rules for large public infrastructure projects like the Bay Bridge. Nancy Pelosi, the Sierra Club and the United Farm Workers have all endorsed him.

    Mark DeSaulnier's campaign, reported by the Independent News

  • He turns up for the votes: 86 missed out of 6,373 roll calls between January 2015 and July 2026, 1.3%, better than the median for sitting members.

    GovTrack voting record

Arguments against

  • He voted in July 2026 for the Massie amendment to cut off aid to Israel — a break with most of his party's leadership that pro-Israel organisations have publicised against the Northern California Democrats who supported it.

    J. The Jewish News of Northern California, reporting the roll call

What we couldn’t verify

  • No published criticism of DeSaulnier by name could be found from Jeffrey Frese's campaign, from his two Democratic primary opponents, from the National Republican Congressional Committee, or from East Bay news coverage; the single argument above rests on a recorded vote reported by a Jewish community outlet rather than on a named critic.
  • DeSaulnier's own explanation of that vote was not established from the sources found.
  • The district's boundaries changed under Proposition 50, approved in November 2025; how that changes his position was not established from the sources found.

What they say they stand for

Their own words. Claims, not verified facts.

  • Cut federal red tape that he says drives up the cost of housing, energy and food.
  • Address rising insurance premiums.
  • Congressional term limits.
  • Election security, including the use of paper ballots.
  • Economic opportunity in California.

What they’ve actually done

Documented record from official sources.

  • Business owner.
  • Has not held elected office.
  • Advanced from the June 2, 2026 top-two primary; the Associated Press called his second-place finish.

Arguments in favor

We found none published about this candidate in the sources reviewed.

Arguments against

We found none published about this candidate in the sources reviewed.

What we couldn’t verify

  • No published criticism of Frese by name could be found: not from Mark DeSaulnier or his campaign, not from the Democratic Congressional Campaign Committee, and not from East Bay news coverage. Because no case against him exists on the record, none is presented for him either, rather than showing his own campaign's case unanswered.
  • He is a small business owner from Moraga; his positions were not stated in material available beyond a candidate questionnaire.
  • His fundraising totals were not reported in material available.

Positions and criticism are quoted from the named sources, not our assessments. This is built to help you start getting informed — confirm the official candidate list with your election authority before you vote.

California's June 2, 2026 top-two primary sent Democratic incumbent Mark DeSaulnier and Republican Jeff Frese to the November ballot; the Associated Press called Frese's second-place finish. Three other candidates were eliminated. The district covers most of Contra Costa County and part of Alameda County and was rated Solid Democratic by the Cook Political Report. Neither candidate is listed with arguments for or against here: no published criticism of either candidate by name from someone opposing them could be found, and setting out a case against one and not the other would tilt the page.

This is one contest on a longer ballot

A California ballot also carries state legislative districts, county offices, judicial seats and often local questions — and which of them you vote on is decided by your street address, not your city or ZIP code.

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