Will the Republican Party win the IL-09 House seat?

The Illinois 9th congressional district’s entrenched Democratic lean, rooted in its northern Chicago and suburban demographics, underpins the 94.5% trader consensus for a Democratic general election victory. Longtime Rep. Jan Schakowsky’s 2025 retirement opened the seat, yet the March 2026 primary produced a strong nominee in Daniel Biss, a former state legislator and Evanston mayor with deep local ties. Republican nominee John Elleson faces structural headwinds in a district that has delivered consistent double-digit Democratic margins. The implied probability reflects this baseline partisan advantage rather than any single event. A realistic shift would require major developments such as a candidate-specific scandal, health crisis, or unusually strong national Republican momentum that alters turnout patterns in this urban-suburban electorate.

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