General election forecast
Grantham and Bourne
Predicted winner: Conservative with 30.0% of the vote, a 0.5pp 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
Gareth Davies
- 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 |
|---|---|---|---|
| Gareth Davies | Conservative and Unionist Party | 16,770 | 36.4% |
| Vipul Bechar | Labour Party | 12,274 | 26.6% |
| Mike Rudkin | Reform UK | 9,393 | 20.4% |
| Anne Elizabeth Gayfer | Green Party | 2,570 | 5.6% |
| John Vincent | Lib Dem | 2,027 | 4.4% |
| Ian Edward Selby | Independent | 1,642 | 3.6% |
| Charmaine Dawn Morgan | Lincolnshire Independents Lincolnshire First | 1,245 | 2.7% |
| Alexander Leslie Mitchell | Social Democratic Party | 204 | 0.4% |
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 Grantham and Bourne, 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 Grantham and Bourne
- 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 37.3% → Reform +2.0pp
- Age-structure adjustment. 65+ 23.1% → Reform +0.20pp, Con +0.08pp (BES-dampened)
- Normalise. Shares scaled to 100%