State Rep. Mark Smith leads the SC-01 Republican primary field with 57.5% implied probability ahead of the June 9 vote, reflecting his state legislative record, early fundraising edge, and top finish in an April GOP forum straw poll. Recent candidate debates on Hilton Head Island sharpened contrasts on redistricting votes and Lowcountry infrastructure, yet Smith's name recognition and alignment with core Republican priorities have sustained his position. Alex Pelbath trails at 8% as the next closest contender, while the remaining candidates, including Jay Byars and Jenny Costa Honeycutt, each register below 6% amid a crowded field that fragments support. Trader consensus factors in the open-seat dynamics after Nancy Mace's gubernatorial bid and the short window to primary day.