In Harry Potter and the Cursed Child, we see that
has become Minister of Magic. This individual was born to muggle parents. Were there any previous muggle-born Ministers of Magic?
According to the Pottermore article on "Ministers for Magic", there has been at least one other:
First Muggle-born Minister for Magic, his appointment caused consternation among the old (pure-blood) guard, many of whom resigned government posts in protest.
However, we don't know if there were any more; the blood statuses of the seven ministers who followed Leach are unknown. It seems plausible that he was the only other, since we also don't hear of any other uproars of the sort that Leach's election was said to have caused, but that's nothing more than a guess.