Clacton by-election: Margin of Victory

Platform comparison

Market context

Nigel Farage's resignation from his Clacton seat has triggered a by-election in one of the safest Conservative strongholds in England. The Essex coastal constituency has returned a Conservative MP at every general election since 1992, though Farage's personal vote share in 2024 exceeded the party machinery's typical performance. The by-election will test whether the Reform UK surge that characterised the general election translates into holding a seat without Farage's direct candidacy, or whether the Conservative Party can reassert control in a constituency it has held for three decades.

The 17% implied probability for a narrow victory margin reflects consensus expectation of a decisive result rather than a close contest. Clacton's electoral history suggests landslide outcomes are the norm: the 2024 general election saw the Conservative candidate win by over 30 percentage points. By-elections in safe seats typically amplify incumbent party advantages when the seat remains with the original party, though Reform's organisational strength and local presence could narrow the gap compared to traditional Conservative dominance. The value question centres on whether traders are overpricing the likelihood of a genuinely competitive race.

Key variables include Reform's candidate selection and campaign intensity, Conservative campaign resource allocation, and turnout patterns in a mid-term by-election environment. The Electoral Commission must formally set the poll date following the Speaker's warrant, typically within three to four months of the vacancy notice. Any significant local issues or national political shifts between now and polling day could alter candidate viability, particularly if either major party signals reduced commitment to the seat.

Methodology

This page reviews Clacton by-election: Margin of Victory across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Who Will Win, which mirrors the Polymarket order book at 0% fees.

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