General election forecast
Sheffield Hallam
Predicted winner: Lib Dem with 29.4% of the vote, a 1.0pp margin over Labour.
Predicted vote share
How the model expects this constituency to vote
Coloured number is the swing from the 2024 general election result.
Sitting MP
Olivia Blake
- Party: Labour Party
- Tenure: 1.9 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 |
|---|---|---|---|
| Olivia Blake | Labour Party | 23,875 | 46.3% |
| Shaffaq Mohammed | Lib Dem | 15,686 | 30.4% |
| Isaac Howarth | Conservative and Unionist Party | 6,205 | 12.0% |
| Jason Leman | Green Party | 4,491 | 8.7% |
| Andrew Hudson Cowell | Social Democratic Party | 654 | 1.3% |
| Sam Chapman | Rejoin EU | 409 | 0.8% |
| Mo Moui-Tabrizy | Workers Party | 281 | 0.5% |
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 Sheffield Hallam, 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 Sheffield Hallam
- 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 yorkshire prior at weight 5%
- English-identity floor. English 30.6% → Reform +2.0pp
- Age-structure adjustment. 65+ 22.0% → Reform +0.20pp, Con +0.08pp (BES-dampened)
- Normalise. Shares scaled to 100%