Daniel Biss, the Democratic nominee and former Evanston mayor who won the March primary, holds a substantial edge in Illinois’ 9th District, a seat with a longstanding Democratic lean following Jan Schakowsky’s retirement. The Republican nominee, John Elleson, faces structural disadvantages in a district rated Solid Democratic by major forecasters, with limited recent polling or campaign developments indicating any meaningful shift in voter preference. Trader pricing on margin outcomes reflects this baseline, concentrating probability on double-digit Democratic victories consistent with historical performance and the absence of competitive national or local catalysts in the final weeks before the November general election. Late-cycle events such as turnout surges or unexpected endorsements could still adjust the final spread within the resolution window.