**John James leads the Michigan Republican primary market at 61% due to his incumbency as a U.S. representative, prior statewide Senate campaigns, and established donor networks that provide organizational advantages heading into the August 4 primary.** A June 16 Mitchell Research poll showed James at 28%, former Attorney General Mike Cox at 27%, and businessman Perry Johnson at 23% among likely GOP voters, marking a statistical dead heat after earlier surveys favored James more clearly. This tightening race, fueled by negative ads targeting James’s record and competition for conservative voter blocs, supports Cox’s 21.5% and Johnson’s 17.5% market shares. Lower-polling candidates such as Senate Minority Leader Aric Nesbitt trail significantly, consistent with their minimal market prices.