State Representative Jermaine Johnson leads Polymarket odds at 74.5% to win the South Carolina Democratic gubernatorial primary on June 9, driven by his top position in the only recent poll of likely Democratic primary voters—a South Carolina Policy Council survey from late January to early February showing him at 25% support versus Mullins McLeod's 8% and 67% undecided. Johnson's edge stems from extensive endorsements by 17 state legislators and the South Carolina AFL-CIO, bolstering his organizational strength in a low-turnout primary expected to favor incumbency name recognition. Late March filings by challengers like McLeod and Billy Webster, coupled with Johnson's refusal to heed reported party pressure to exit, have reinforced trader consensus on his frontrunner status, while McLeod's 16.5% reflects his prior 2010 candidacy but limited backing.