If you’ve ever watched a BBC election broadcast, you’ve seen its legendary Swingometer, moving the dial until one party or the other took control of Parliament. It tried to answer a simple question: given a uniform swing in the national vote, how many seats shift?
Of course, the idea of uniform swing was always too simplistic. Seats don’t swing uniformly. Demographics and candidate quality make them swing differently. We need a Swingometer that does the same. So I decided to build one.
The Intersection’s 2026 Swingometer starts with Democrats winning a 224-211 majority in the House based on today’s D+6.0 generic ballot polling average. Unlike the swingometers of old, not every seat to the left or right of the dial is the same color. Seats vary based on demonstrated track records of over- and under-performance and a few penalties added for ideological extremity or controversy.
