Open seats are where most of the action is. Incumbency is one of the strongest predictors of an election outcome — but when the incumbent retires, is term-limited, runs for higher office, or otherwise leaves the ballot, the seat resets. Open seats are disproportionately likely to flip, draw competitive primaries, and produce next-cycle leaders.
This page tracks every state-level general or special election we have on file where no incumbent appeared on the ballot. Use the chart to see which cycles produced the most open contests (redistricting cycles like 2012 and 2022 spike, since reshuffled boundaries effectively create new seats). Browse the full list below, filterable by state, chamber, year, and whether the open seat ultimately flipped parties. Click any row to see the underlying election.
Open Seats by Cycle
Number of general/special elections held without an incumbent on the ballot. Stacked by outcome (flipped vs. held).
Browse All Open Seats
All Open Seats
| Year | State | District | Winner | Prior Holder | Outcome | Margin |
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Methodology
An "open seat" is a general or special election where no candidate on the ballot was flagged as an incumbent in our database. The incumbent may have retired, been term-limited, run for a different office, switched parties and not run again, died, or otherwise left the seat between cycles. From the perspective of voters at the ballot box, every candidate is new to the office.
Prior holder and flip detection. We compare the winner's party to the party of the seat's immediately preceding officeholder (from seat_terms). When those parties differ, the open seat "flipped" — labeled accordingly in the table. When they match, the same party held the seat through the transition.
Coverage window. 2010 forward, the period where our 50-state coverage is substantially complete. Pre-2018 incumbency flags are still being backfilled for some states, so historical totals may shift slightly as that data improves.
Why open seats matter. Open seats see higher candidate counts, more competitive primaries, more campaign spending, and meaningfully higher flip rates than incumbent-defended seats. Redistricting cycles (2012, 2022) and the cycles immediately following large wave years tend to produce more open seats — incumbents who barely survived a wave often retire ahead of the next election.