Stefany Shaheen holds the leading position in the New Hampshire 1st Congressional District Democratic primary due to her established local profile as a former Portsmouth city councilor and police commission chair, along with a series of recent mayoral endorsements across key communities including Portsmouth, Dover, Rochester, and Somersworth. These developments have helped consolidate support ahead of the September 8 primary for the open seat. Maura Sullivan, a Marine veteran and former Defense Department official, remains competitive through strong fundraising and military background, while Carleigh Beriont and Heath Howard draw from local governance and progressive organizing efforts respectively. Candidate forums in May highlighted shared priorities on housing, healthcare, and affordability, with no major shifts reported in the past month.