General election forecast
South Leicestershire
Predicted winner: Reform UK with 29.1% of the vote, a 0.1pp margin over Conservative.
Predicted vote share
How the model expects this constituency to vote
Coloured number is the swing from the 2024 general election result.
Sitting MP
Alberto Costa
- 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 |
|---|---|---|---|
| Alberto Costa | Conservative and Unionist Party | 18,264 | 35.6% |
| Robert Parkinson | Labour Party | 12,758 | 24.8% |
| Bill Piper | Reform UK | 10,235 | 19.9% |
| Paul Hartshorn | Lib Dem | 7,621 | 14.8% |
| Mike Jelfs | Green Party | 2,481 | 4.8% |
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 Leicestershire, 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 Leicestershire
- 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 east_midlands prior at weight 5%
- English-identity floor. English 39.8% → Reform +2.0pp
- Age-structure adjustment. 65+ 20.9% → Reform +0.20pp, Con +0.08pp (BES-dampened)
- Normalise. Shares scaled to 100%