John E. Sununu maintains a commanding lead in the New Hampshire Republican Senate primary due to his prior service representing the state in the chamber from 2003 to 2009, deep family political roots, consistent double-digit polling advantages over Scott Brown, and key endorsements including from President Trump. Recent surveys through mid-August show Sununu at 54-59% among likely Republican primary voters, with Brown trailing in the low-to-mid 20s and minor candidates far behind, while Sununu also posts stronger general-election positioning against Democrat Chris Pappas than Brown. Dan Innis withdrew and endorsed Sununu, further consolidating support ahead of the September 8 vote. Scenarios that could still alter the outcome include unforeseen late developments such as health events or major scandals in the final weeks, though the primary electorate has shown little movement toward alternatives.