**Trader consensus heavily favors 4-6 Republican House incumbents losing their primaries (95.2% implied probability), reflecting the limited number of defeats recorded so far in the 2026 cycle and the absence of widespread additional challenges.** Several factors explain this positioning. Historical patterns show low incumbent primary defeat rates in non-redistricting-heavy cycles, typically averaging around 6-7 total House losses across both parties. In 2026, redistricting in states like Texas contributed to early losses, including Rep. Dan Crenshaw, while targeted Trump-endorsed challenges ousted critics such as Rep. Thomas Massie. Other defeats, including Reps. Andy Ogles and Cory Mills, stemmed from scandals, local dynamics, or campaign issues rather than a broad wave. Reports through September 2026 indicate roughly four Republican House primary losses total, consistent with or slightly above postwar averages but far from record levels. With most primaries concluded by mid-to-late 2026 and no major late-cycle disruptions reported in remaining contests, the market prices in at most one or two additional defeats. A shift toward 7-9 would require several unexpected high-profile upsets in battleground primaries, which have not materialized amid the cycle's focus on general election dynamics and internal polling showing broader general election vulnerabilities instead.