CA-48 · U.S. House
Marni von Wilpert is favored to flip California’s 48th congressional district. Predicted margin: D+5.2.
Under each share, its likely range (80 in 100 simulations)
Forecast history
Latest reading · Oct 28 · first published Sep 9 · 80% range · margin points R+2.3 to D+12.8. Methodology
About this series
Reconstructed with the current model Aug 1 – Sep 8 and Sep 16 – Sep 18; published readings Sep 9 – Oct 28. Each reconstructed day is the current model on that day’s own inputs, not a forecast published then. Corrections are dated in the changelog.
Faded: CTMM 2.2 reconstructed history: computed after the fact with each date's available polls and environment, without expert ratings; not an issued forecast. Issued forecasts begin at the launch marker.
CTMM 2.2 readings for 2026-09-16, 2026-09-17, 2026-09-18 were computed after the fact with each day's available inputs: no edition was issued on those days. Not an issued forecast.
Data table
| Date | Margin | Chance | 80% range | Reading |
|---|---|---|---|---|
| Oct 28 | D+5.2 | D win 82.0% | R+2.3 to D+12.8 | Published forecast |
| Oct 27 | D+6.5 | D win 86.2% | R+1.2 to D+14.3 | Published forecast |
| Oct 26 | D+6.5 | D win 86.2% | R+1.3 to D+14.3 | Published forecast |
| Oct 25 | D+6.5 | D win 86.1% | R+1.3 to D+14.3 | Published forecast |
| Oct 24 | D+6.5 | D win 86.1% | R+1.3 to D+14.3 | Published forecast |
| Oct 23 | D+7.2 | D win 87.7% | R+0.8 to D+15.2 | Published forecast |
| Oct 22 | D+7.2 | D win 87.7% | R+0.8 to D+15.2 | Published forecast |
| Oct 21 | D+7.2 | D win 87.6% | R+0.9 to D+15.2 | Published forecast |
| Oct 20 | D+7.1 | D win 87.5% | R+0.9 to D+15.1 | Published forecast |
| Oct 19 | D+7.1 | D win 87.4% | R+0.9 to D+15.1 | Published forecast |
| Oct 18 | D+7.1 | D win 87.3% | R+0.9 to D+15.1 | Published forecast |
| Oct 17 | D+7.1 | D win 87.3% | R+1.0 to D+15.1 | Published forecast |
| Oct 16 | D+7.0 | D win 87.0% | R+1.0 to D+15.0 | Published forecast |
| Oct 15 | D+7.0 | D win 86.9% | R+1.0 to D+15.0 | Published forecast |
| Oct 14 | D+7.0 | D win 86.9% | R+1.1 to D+15.0 | Published forecast |
| Oct 13 | D+6.9 | D win 86.8% | R+1.1 to D+15.0 | Published forecast |
| Oct 12 | D+6.9 | D win 86.7% | R+1.1 to D+14.9 | Published forecast |
| Oct 11 | D+6.9 | D win 86.7% | R+1.1 to D+14.9 | Published forecast |
| Oct 10 | D+6.9 | D win 86.7% | R+1.1 to D+14.9 | Published forecast |
| Oct 9 | D+6.9 | D win 86.5% | R+1.2 to D+14.9 | Published forecast |
| Oct 8 | D+5.4 | D win 80.8% | R+2.7 to D+13.5 | Published forecast |
| Oct 7 | D+5.4 | D win 80.6% | R+2.8 to D+13.5 | Published forecast |
| Oct 6 | D+5.3 | D win 80.4% | R+2.8 to D+13.4 | Published forecast |
| Oct 5 | D+5.3 | D win 80.1% | R+2.9 to D+13.4 | Published forecast |
| Oct 4 | D+5.3 | D win 80.1% | R+2.9 to D+13.4 | Published forecast |
| Oct 3 | D+5.2 | D win 79.9% | R+2.9 to D+13.4 | Published forecast |
| Oct 2 | D+5.2 | D win 79.9% | R+2.9 to D+13.3 | Published forecast |
| Oct 1 | D+5.2 | D win 79.8% | R+3.0 to D+13.3 | Published forecast |
| Sep 30 | D+5.2 | D win 79.6% | R+3.0 to D+13.3 | Published forecast |
| Sep 29 | D+5.1 | D win 79.4% | R+3.0 to D+13.3 | Published forecast |
| Sep 28 | D+5.1 | D win 79.3% | R+3.1 to D+13.2 | Published forecast |
| Sep 27 | D+5.0 | D win 79.0% | R+3.1 to D+13.2 | Published forecast |
| Sep 26 | D+5.0 | D win 79.0% | R+3.1 to D+13.2 | Published forecast |
| Sep 25 | D+5.0 | D win 79.0% | R+3.1 to D+13.2 | Published forecast |
| Sep 24 | D+5.0 | D win 78.7% | R+3.2 to D+13.1 | Published forecast |
| Sep 23 | D+4.9 | D win 78.4% | R+3.2 to D+13.1 | Published forecast |
| Sep 22 | D+4.8 | D win 77.9% | R+3.3 to D+13.0 | Published forecast |
| Sep 21 | D+4.8 | D win 77.9% | R+3.3 to D+13.0 | Published forecast |
| Sep 20 | D+4.8 | D win 78.1% | R+3.3 to D+13.0 | Published forecast |
| Sep 19 | D+4.8 | D win 78.0% | R+3.3 to D+13.0 | Published forecast |
| Sep 18 | D+4.8 | D win 78.1% | R+3.3 to D+13.0 | Reconstructed with the stated inputs |
| Sep 17 | D+4.8 | D win 77.9% | R+3.4 to D+12.9 | Reconstructed with the stated inputs |
| Sep 16 | D+4.8 | D win 77.8% | R+3.4 to D+12.9 | Reconstructed with the stated inputs |
| Sep 15 | D+4.6 | D win 77.1% | R+3.5 to D+12.8 | Published forecast |
| Sep 14 | D+4.6 | D win 77.2% | R+3.5 to D+12.8 | Published forecast |
| Sep 13 | D+4.6 | D win 77.1% | R+3.5 to D+12.8 | Published forecast |
| Sep 12 | D+4.6 | D win 77.0% | R+3.6 to D+12.8 | Published forecast |
| Sep 11 | D+4.6 | D win 76.5% | R+3.6 to D+12.7 | Published forecast |
| Sep 10 | D+4.5 | D win 76.7% | R+3.6 to D+12.7 | Published forecast |
| Sep 9 | D+4.5 | D win 76.6% | R+3.7 to D+12.7 | Published forecast |
| Sep 8 | D+4.5 | D win 76.3% | R+3.7 to D+12.6 | Reconstructed with the stated inputs |
| Sep 7 | D+4.4 | D win 76.1% | R+3.8 to D+12.6 | Reconstructed with the stated inputs |
| Sep 6 | D+4.4 | D win 76.0% | R+3.8 to D+12.6 | Reconstructed with the stated inputs |
| Sep 5 | D+3.5 | D win 71.5% | R+4.6 to D+11.5 | Reconstructed with the stated inputs |
| Sep 4 | D+3.4 | D win 71.3% | R+4.6 to D+11.5 | Reconstructed with the stated inputs |
| Sep 3 | D+3.7 | D win 71.9% | R+4.6 to D+12.0 | Reconstructed with the stated inputs |
| Sep 2 | D+3.6 | D win 71.7% | R+4.7 to D+11.9 | Reconstructed with the stated inputs |
| Sep 1 | D+3.6 | D win 71.6% | R+4.7 to D+11.9 | Reconstructed with the stated inputs |
| Aug 31 | D+3.6 | D win 71.5% | R+4.7 to D+11.9 | Reconstructed with the stated inputs |
| Aug 30 | D+3.6 | D win 71.3% | R+4.8 to D+11.9 | Reconstructed with the stated inputs |
| Aug 29 | D+3.5 | D win 71.2% | R+4.8 to D+11.8 | Reconstructed with the stated inputs |
| Aug 28 | D+3.5 | D win 71.0% | R+4.8 to D+11.8 | Reconstructed with the stated inputs |
| Aug 27 | D+3.5 | D win 70.9% | R+4.8 to D+11.8 | Reconstructed with the stated inputs |
| Aug 26 | D+3.4 | D win 70.6% | R+4.9 to D+11.8 | Reconstructed with the stated inputs |
| Aug 25 | D+3.4 | D win 70.6% | R+4.9 to D+11.7 | Reconstructed with the stated inputs |
| Aug 24 | D+3.4 | D win 70.4% | R+4.9 to D+11.7 | Reconstructed with the stated inputs |
| Aug 23 | D+3.4 | D win 70.3% | R+5.0 to D+11.7 | Reconstructed with the stated inputs |
| Aug 22 | D+4.0 | D win 73.8% | R+4.3 to D+12.3 | Reconstructed with the stated inputs |
| Aug 21 | D+4.0 | D win 73.4% | R+4.3 to D+12.3 | Reconstructed with the stated inputs |
| Aug 20 | D+4.0 | D win 73.3% | R+4.3 to D+12.3 | Reconstructed with the stated inputs |
| Aug 19 | D+4.0 | D win 73.2% | R+4.4 to D+12.3 | Reconstructed with the stated inputs |
| Aug 18 | D+3.9 | D win 73.1% | R+4.4 to D+12.3 | Reconstructed with the stated inputs |
| Aug 17 | D+3.9 | D win 72.9% | R+4.4 to D+12.2 | Reconstructed with the stated inputs |
| Aug 16 | D+3.9 | D win 72.8% | R+4.5 to D+12.2 | Reconstructed with the stated inputs |
| Aug 15 | D+3.9 | D win 72.7% | R+4.5 to D+12.2 | Reconstructed with the stated inputs |
| Aug 14 | D+3.8 | D win 72.3% | R+4.5 to D+12.1 | Reconstructed with the stated inputs |
| Aug 13 | D+3.8 | D win 72.2% | R+4.5 to D+12.1 | Reconstructed with the stated inputs |
| Aug 12 | D+3.8 | D win 72.1% | R+4.6 to D+12.1 | Reconstructed with the stated inputs |
| Aug 11 | D+3.7 | D win 72.0% | R+4.6 to D+12.1 | Reconstructed with the stated inputs |
| Aug 10 | D+3.7 | D win 71.8% | R+4.6 to D+12.1 | Reconstructed with the stated inputs |
| Aug 9 | D+3.7 | D win 71.7% | R+4.6 to D+12.0 | Reconstructed with the stated inputs |
| Aug 8 | D+3.7 | D win 71.5% | R+4.7 to D+12.0 | Reconstructed with the stated inputs |
| Aug 7 | D+3.7 | D win 71.4% | R+4.7 to D+12.0 | Reconstructed with the stated inputs |
| Aug 6 | D+3.6 | D win 71.1% | R+4.7 to D+11.9 | Reconstructed with the stated inputs |
| Aug 5 | D+3.6 | D win 71.0% | R+4.8 to D+11.9 | Reconstructed with the stated inputs |
| Aug 4 | D+3.6 | D win 70.9% | R+4.8 to D+11.9 | Reconstructed with the stated inputs |
| Aug 3 | D+3.5 | D win 70.8% | R+4.8 to D+11.9 | Reconstructed with the stated inputs |
| Aug 2 | D+3.5 | D win 70.7% | R+4.8 to D+11.8 | Reconstructed with the stated inputs |
| Aug 1 | D+3.5 | D win 70.6% | R+4.8 to D+11.8 | Reconstructed with the stated inputs |
The polls
Poll average D+4.6A poll’s weight halves every 60 days and grows with its sample. Each pollster counts once, at its best release. Every poll counts at its published margin, sponsored or not.In House races the forecast then counts a poll sponsored by a party or campaign at full weight and moves its margin 2 points against that party, which puts the average it reads at D+4.1.5 recorded polls · 5 in the poll average
| Fieldwork | Added | Pollster | Result | Sample |
|---|---|---|---|---|
| from 2026-10-20 | 13h ago | RedBox Research (D) ↗ | D+5.0D 48% · R 43% | 1,151 LV |
| from 2026-10-17 | 5d ago | Tarrance Group ↗ | D+3.0D 47% · R 44% | 410 LV |
| from 2026-10-01 | SurveyUSA ↗KGTV-TV (California) | San Diego Union-Tribune | D+9.0D 47% · R 38% | 518 LV | |
| from 2026-08-27 | SurveyUSA ↗KGTV-TV (California) | San Diego Union-Tribune | D+3.0D 45% · R 42% | 522 LV | |
| from 2026-07-09 | Lake Research Partners ↗ | D+2.0D 48% · R 46% | 500 LV |
Explore each poll’s weight in the average
Poll average D+4.6
- Published result
- D+5.0
- Weight in the poll average
- 0.87 · 43% of the average
- Fieldwork
- 20 Oct–23 Oct
- Sample
- 1,151 LV
- Sponsor
- Democratic sponsor · organization not listed
- Published result
- D+3.0
- Weight in the poll average
- 0.50 · 25% of the average
- Fieldwork
- 17 Oct–20 Oct
- Sample
- 410 LV
- Sponsor
- Republican sponsor · organization not listed
- Published result
- D+9.0
- Weight in the poll average
- 0.49 · 14% of the average
- Fieldwork
- 1 Oct–7 Oct
- Sample
- 518 LV
- Sponsor
- KGTV-TV (California) | San Diego Union-Tribune
- Published result
- D+3.0
- Weight in the poll average
- 0.32 · 9.5% of the average
- Fieldwork
- 27 Aug–1 Sep
- Sample
- 522 LV
- Sponsor
- KGTV-TV (California) | San Diego Union-Tribune
- Published result
- D+2.0
- Weight in the poll average
- 0.18 · 8.8% of the average
- Fieldwork
- 9 Jul–14 Jul
- Sample
- 500 LV
- Sponsor
- DEM sponsor · organization not listed
Where the votes are
The map of this race loads here.
Recent elections
| Election | Result | Votes cast |
|---|---|---|
| 2024 · U.S. House ↗ | R+18.6 | 360,290 |
| 2022 · U.S. House ↗ | R+20.7 | 257,071 |
| 2020 · U.S. House ↗ | R+2.1 | 395,100 |
| 2018 · U.S. House ↗ | D+7.1 | 294,736 |
Historical district boundaries may differ. Margins are the Democrat’s share of all votes cast minus the Republican’s.
The money
Jim Desmond ↗
R$2.3Mraised
$1.2M cash on hand
Marni von Wilpert ↗
D$2.2Mraised
$825K cash on hand
The tick marks cash on hand. A missing filing stays blank rather than becoming $0.
One more fundraising reportCall the Map · $325
The candidates are comfortably out-fundraising the website covering them. A little rude, perhaps, but statistically unsurprising.
- Received so far
- $325
- Measured compute
- $26,188.58
Ko-fi and Buy Me a Coffee supports are counted as each one arrives. Measured compute prices model runs at standard published API rates; it is not what I paid. Hosting, data and subscriptions, the domain and my own time are not counted. Donations buy gratitude, never a forecast adjustment.
Supporters are listed by first name and last initial; a username alone is shortened to its first eight characters. Want your full name shown? Say so in your message. Give privately, or leave the name blank, and you are listed as Anonymous, with the platform and date. Supporters who give a name may also be thanked by name in the newsletter.
Thank you to Tom H., ColoradoFlyer, Chris, EW, gbaileym…, True Independent, MT V., JBL, Erin G., Caroline M., Melanie, MKV and 7 more.
Outside spending
Separate from what the campaigns raisedFor and against Marni von Wilpert$3.1M
15 spending groups
| Group | For | Against |
|---|---|---|
| Project 218 | $900K | $0 |
| Serving CA | $0 | $653K |
| Equality PAC | $479K | $0 |
| Elect Democratic Women | $390K | $0 |
| NO GOING BACK PAC INC. | $0 | $196K |
| Women Vote | $139K | $0 |
| Health Care Saves Lives | $93K | $0 |
| Worker Power PAC | $71K | $0 |
| MAGA INC. | $0 | $67K |
| VETERANS FOR TRUTH PAC | $0 | $52K |
| SEIU COPE (Service Employees International Union Committee On Political Education) | $49K | $0 |
| AB PAC | $25K | $0 |
| CIVIC RENEWAL FUND INC. | $0 | $16K |
| DEMOCRATIC MESSAGING PROJECT | $10K | $0 |
| VOTERS OF TOMORROW PAC | $3K | $0 |
For and against Jim Desmond$4.7M
6 spending groups
| Group | For | Against |
|---|---|---|
| HMP | $0 | $3.8M |
| 48Th Accountability Project | $0 | $337K |
| Health Care Saves Lives | $0 | $265K |
| NO GOING BACK PAC INC. | $134K | $0 |
| CIVIC RENEWAL FUND INC. | $81K | $0 |
| Equality PAC | $0 | $45K |
Includes primary spending. Opposition is recorded against its named target; no benefit to another candidate is assumed.
$3.8M in outside spending on earlier candidates.
FEC filings · through 06/30/2026 · Definitions & method
Race context
- 2024 presidential vote here
- 328,054
- 2024 presidential margin
- D+3.5between the two parties
Forecast as of October 28, 2026: Call the Map currently has Marni von Wilpert ahead of Jim Desmond by D+5.2, with an 82 in 100 chance to win. This is an open seat. That result would flip the seat to Democrats. The current poll average is D+4.6; 5 public polls are recorded.