Incumbent Republican Mike Simpson faces Democrat Ellie Gilbreath in Idaho's 2nd congressional district on November 3, 2026, in a seat rated solid or safe Republican by major forecasters. Simpson's long tenure, primary win with 63 percent, and $1.4 million fundraising edge contrast with Gilbreath's lower profile and $169,000 raised, while a late October poll showed Simpson at 46 percent to her 31 percent. Trader pricing concentrates probability on Republican margins of 15-25 percent because the district's eastern rural and Boise-area base favors consistent GOP performance, yet exact spread remains sensitive to turnout, independent and third-party vote splits, and any final-week shifts in voter engagement. Low national attention and few late developments keep the outcome range fluid until election results finalize.