If the number of Republican Senate members that lose their primary in 2026 before Nov 3, 2026 is at least 4, then the market resolves to Yes. To be included, candidates must: 1. Be running in an election for the office they currently hold (regardless of District), for a party they are currently in, as of primary day for the seat they're contesting in in 2026; 2. Be running for the nomination of a position whose election day is on the same date as most Congressional elections in 2026, typically an early Tuesday of November; 3. Lose the Republican primary for that election to another candidate. In jurisdictions with non-partisan or "top-two" primary systems, an incumbent is not considered to have lost if they advance to the General Election ballot, regardless of their placement relative to other advancing candidates. For the purposes of determining eligibility, a candidate is considered to be running for the "office they currently hold" if they are seeking re-election to the same legislative body (House or Senate), regardless of changes to their specific district number or geographic constituency. In the event that primaries for an unexpired term (Special Election) and the next full term (General Election) are held concurrently, the Payout Criterion applies exclusively to the results of the primary for the next full term. This market will close and expire early if the number of primary losses exceeds the cap or is mathematically guaranteed to fall within a specific range before the expiration date.