Stefany Shaheen leads the New Hampshire 1st Congressional District Democratic primary, scheduled for September 8, 2026, with strong name recognition as the daughter of longtime U.S. Senator Jeanne Shaheen and prior service on the Portsmouth city council. Traders reflect this advantage in her 68.5 percent implied probability through consistent polling leads, superior in-state donor support, and broad party endorsements. Maura Sullivan, a Marine Corps veteran and former Obama administration official who previously sought the seat in 2018, holds second place at 28.5 percent on the strength of substantial fundraising and grassroots outreach focused on affordability and veterans' issues. State Representative Heath Howard and Carleigh Beriont trail at 3.9 percent and 1.6 percent, respectively, limited by lower visibility and resources in the nine-candidate field. The short remaining campaign window leaves limited scope for major momentum shifts before ballots are cast.