The Delaware Republican Party's recent state convention endorsement has positioned Michael Katz as the frontrunner for the September 15, 2026, U.S. Senate primary, reflecting trader consensus around his established name recognition from prior service in the state Senate and crossover appeal as a former Democrat. John Shulli trails despite stronger campaign fundraising through the first quarter of 2026, as the official party backing provides Katz with institutional support that often proves decisive in low-turnout primaries. With no incumbent in the race and limited polling available, market pricing highlights the endorsement's weight against Shulli's profile as a U.S. Army War College instructor and his early organizational efforts. Both candidates remain active ahead of the filing deadline, and any shifts in party alignment or additional endorsements could still influence final positioning before voters decide.