Michael Katz leads the Delaware Republican U.S. Senate primary with 81.5% implied probability due to unified party establishment support, including the state GOP endorsement, multiple state legislator backings, and an 82% victory at the April 2026 state convention. His prior service as a Democratic state senator, 2024 independent Senate run, physician background, and stronger fundraising—with nearly $98,000 cash on hand as of late August—underscore broader coalition appeal ahead of the September 15 primary. John Shulli, at 17.5%, draws on his Army colonel experience and endorsements from figures like Michael Flynn but trails in institutional support and resources. The closely timed contest leaves limited room for late shifts in voter sentiment.