Raymond McKay holds an 84.5% implied probability as the frontrunner in the Rhode Island Republican U.S. Senate primary, driven by his commanding fundraising lead—over $150,000 raised versus Allen Waters' under $30,000—and endorsements from the state Republican Party following its August convention. Traders view these advantages as decisive in the low-turnout primary on September 10, where GOP primaries often favor the establishment-backed candidate amid sparse polling and limited challenger momentum. Waters lingers at 12.3% on minor visibility gains from local events, but no recent developments like debates or scandals have narrowed the gap, with bettors pricing in minimal upset risk barring late voter surges or absentee ballot shifts.