Upset Brief · CA-18 · Shane Lewis (R) vs. Zoe Lofgren (D), incumbent
A long shot on the math: it takes a 27.9-point national wave.
0%
odds today
0%
odds with the plan
45,623
net votes to find
37
days left; voting starts October 5
Where
- 01+258San JoseStarting line Lofgren +48. 1.1% split their ticket.
- 02+204Morgan HillStarting line Lofgren +23. 2.1% split their ticket.
- 03+176SalinasStarting line Lofgren +29. 1.1% split their ticket.
- 04+160HollisterStarting line Lofgren +20. 2.6% split their ticket.
- 05+143GilroyStarting line Lofgren +26. 1.5% split their ticket.
- 06+107CoalingaStarting line Lewis +19. 2.2% split their ticket. About 1,186 more ballots in 2024 than in 2022 (estimate).
The top 12 cities and unincorporated areas carry 94% of the plan.
How
- P+1,219Persuade1,219 voters who split their ticket in recent elections and lean Lofgren today.
- M+74MobilizeAt least 1,193 people who voted in 2024 but not in 2022, in cities and unincorporated areas where Lewis's side wins at least 55 percent.
- C+241ConsolidateVoters who went third party in recent races, in the cities and unincorporated areas that lean Lewis's way.
Plus a national shift of 27.9 points of margin (44,090 votes) that no campaign controls.
What has to be true
- Lewis wins 50 percent of the ticket splitters now leaning Lofgren.
- In Coalinga, 35 percent of the people who voted in 2024 but skipped 2022 come back and vote.
- The national environment moves about 27.9 points toward Lewis's side between now and November 3.
- No 2026 public poll exists for this race, so the starting line is a weighted blend of official recent results; the first real poll will move it.
The numbers behind it
- 01Crossover regression431 precincts, R² 0.965, 81 crossover precincts identified
- 02Monte Carlo20,000 seeded simulated elections with a 7-point baseline error. 90% range of the final margin with the plan: -62,313 to -25,904 votes.
- 03Money, FEC candidate totals through June 30Lewis $3,307 cash on hand; Lofgren $643,341.
- 04Call program for this list2,981 households, 8,943 dials, about 469 live conversations: an estimated $1,701 at published rates.
Independent analysis by The Political Group from official California Secretary of State precinct returns (2022 and 2024), FEC filings and published polls, as of September 26, 2026. Not affiliated with any candidate or party.