Michael Katz holds an 80% implied probability in the Delaware Republican Senate primary due to his prior service as a state senator representing a Wilmington district from 2009 to 2013, which provides established name recognition and legislative experience within the state. John Shulli, a retired Army colonel and current instructor at the U.S. Army War College with extensive military and national security background, trails at 18% as a first-time candidate. Both filed for the September 15, 2026 primary earlier this year with limited subsequent developments reported, leaving voter familiarity and fundraising patterns as primary factors shaping trader assessments ahead of the low-turnout contest.