Generic ballot

How the generic ballot is reported

The question asks whether a voter would back the Democratic or the Republican candidate for Congress in their district, with the exact wording varying by pollster. Results are reported as each party’s share and as a margin. In the worked example, D 48% / R 44% is a four-point Democratic lead, usually written D+4. The remaining 8% is undecided or other.

A single poll carries sampling error and reflects one pollster’s method, so the generic ballot is often followed as an average across several polls. Movement in that average over weeks says more than any one release.

Why the national number doesn’t map onto seats

House seats are won district by district. Where each party’s voters live, how district lines are drawn, which seats have incumbents and which races are uncontested all shape how a national vote share turns into seats. A party can lead the national vote and still fall short of 218 seats, or trail it narrowly and hold a majority.

That’s why the 52¢ contract in the example sits above the 48% poll figure rather than equal to it. The two numbers measure different things: the poll is a share of stated vote intention, and the contract price is an implied probability that one party ends up with a majority. The Senate is further removed again, since only about a third of its seats are on the ballot in any election.

A contract on the generic ballot itself, where one is listed, asks about a poll reading rather than about seats. It settles on whichever polling measure and date its rules name, which is a different source from the one a balance of power contract uses: the election results its rules name, which can allow settling early once major news organizations have called the races and no recount or challenge is pending.