Forecast archive

HOW TO READ THE ARCHIVE

Seat estimates and race-by-race movement

Expected seat totals add each forecast race’s party win chances. They can include fractional seats because they represent averages across outcomes. Current seat ranges are shown only where a saved distribution is available. Race comparisons show the winner call, whether the site’s Toss-up/Lean/Likely/Safe category changed, Democratic-margin change, and Democratic win-chance change.

Changes are calculated as the newer release minus the immediately older saved release. Winner calls use the higher party probability. Rating bands are Toss-up below 60%, Lean from 60% to below 80%, Likely from 80% to below 98%, and Safe at 98% or higher for the stronger party. Senate totals combine 35 forecast contests with 65 seats not up for election. Governor totals cover the 36 races on the ballot, not all 50 states. Older releases have differences in source dates and inputs, so changes between dates should be read as descriptive comparisons rather than the effect of new polls alone.

For retrospective comparisons with polling averages and actual results, see the History page.