Former U.S. Senator John E. Sununu holds an 88.5% implied probability in the New Hampshire Republican Senate primary due to his strong local name recognition, prior service in the seat, and endorsement from President Trump in February. A late-April University of New Hampshire poll showed him leading former Massachusetts Senator Scott Brown 56% to 19% among likely GOP primary voters. Sununu's fundraising edge, with nearly $1.9 million cash on hand compared to Brown's roughly $783,000, has further widened his advantage ahead of the September 8 primary. Brown continues to campaign on independence and border security as an outsider, while lower-probability options like Chris Sununu and Dan Innis reflect limited recent activity or withdrawal from the field.