General election forecast
South West Devon
Predicted winner: Conservative with 27.9% of the vote, a 0.4pp margin over Reform UK.
Predicted vote share
How the model expects this constituency to vote
Coloured number is the swing from the 2024 general election result.
Sitting MP
Rebecca Smith
- Party: Conservative and Unionist Party
- Tenure: 2.1 years (since 2024-07-04)
- Status: standing again
See also: TheyWorkForYou
2024 general election result
What happened on 4 July 2024
| Candidate | Party | Votes | Share |
|---|---|---|---|
| Rebecca Smith | Conservative and Unionist Party | 17,916 | 34.3% |
| Sarah Allen | Labour Party | 15,804 | 30.3% |
| Steve Horner | Reform UK | 9,361 | 17.9% |
| Julian Brazil | Lib Dem | 5,551 | 10.6% |
| Lauren McLay | Green Party | 2,925 | 5.6% |
| Alan Charles Spencer | Independent | 438 | 0.8% |
| Ben Davy | Trade Unionist and Socialist Coalition | 141 | 0.3% |
| Darryl Christian Ingram | Heritage Party | 106 | 0.2% |
Source: Returning officer declaration
How accurate is the model here?
Our 2024 backtest for this constituency
We replayed the same model architecture against the 4 July 2024 general election using only the data a forecaster running the model in May 2024 would have known. Here's what it would have predicted for South West Devon, and what actually happened.
Predicted
Actual on 4 July 2024
Positive gap = we predicted that party would win more share than they did. See the full GE backtest across all 650 seats for the model's national accuracy.
How this forecast was built
- GE2024 Baseline. Actual GE2024 result in South West Devon
- National Swing (Strong Transition Model). Multiplicative bounded swing, losers shed in proportion to local share, gainers absorb pro-rata national gain. Replaces additive UNS.
- BES MRP Prior. Baseline blended with BES Wave 1-30 south_west prior at weight 5%
- English-identity floor. English 35.2% → Reform +2.0pp
- Age-structure adjustment. 65+ 24.9% → Reform +0.20pp, Con +0.08pp (BES-dampened)
- Normalise. Shares scaled to 100%