Delaware’s at-large House seat remains a structural Democratic stronghold ahead of the November 3 general election, with incumbent Sarah McBride facing Republican nominee Joseph Arminio. The district’s consistent D+15 partisan lean, driven by New Castle County demographics, has produced double-digit Democratic margins in recent cycles, including McBride’s 2024 victory. Nonpartisan forecasters rate the race Solid or Safe Democratic, reflecting the absence of competitive polling movement or credible opposition following September primaries. Traders’ near-certain pricing for a Democratic win aligns with these fundamentals and historical base rates for the seat. Only late developments such as a major scandal, health event, or unprecedented national wave would realistically alter the outcome before Election Day.