S.C. Governor Candidate Shouts N-Word in Cop Car on New Body Cam Arrest Video

An attorney in South Carolina who's running for governor -- whose arrest may have already tanked his shot -- is finding himself in an even deeper hole now that full body cam video of his arrest is out ... showing him dropping the N-word.

TMZ obtained the clip from the Charleston Police Department -- William "Mullins" McLeod Jr., who’s gunning for the Palmetto State's 2026 gubernatorial seat -- casually tosses in the racial slur during his loud, expletive-packed tirade ... before, ironically, saying, "I better start paying more attention to this racist ass Donald Trump."

It gets wilder -- 'cause during his May arrest for disorderly conduct, a Taylor Swift song starts playing in the background. First up, her 2012 hit "I Knew You Were Trouble" (fitting, right?), followed by "Wildest Dreams" ... which was pretty on point too, 'cause things were spiraling fast!

McLeod keeps rambling at the top of his lungs -- yelling about going to the moon if he had a billion bucks, taking a s***, Rolls-Royces, and a bunch more nonsense ... all while optimistically yelling, "When I’m governor ..."

Of course, the odds of that happening now are basically nil -- especially after dropping the N-word in a state with a large Black population.

McLeod -- the first Democrat to throw his hat in the ring for a shot at Gov. Henry McMaster’s seat -- now has his team in full scramble mode. They've told TMZ he’ll be holding a press conference to address the damning video ... but at this point, his whole campaign appears to be hanging by a thread.