No Republican candidate in the 2018 midterms embodies so many contradictions as pointedly as Mr. Blankenship, who was found guilty of conspiracy to violate mine safety standards in federal court and yet has plenty of supporters in coal country.

He is one of three leading Republican contenders heading into the primary, even though he is lugging around enough political baggage to disqualify a candidate most anywhere else.

That Mr. Blankenship retains a political hope is a consequence of West Virginia’s sharp shift to the right, driven by seething hostility to the Obama presidency, both its social changes and its perceived “war” on coal. The emergence of a former coal boss with a criminal record as a potential Senate nominee seems partly an expression of many West Virginia voters’ desire to poke a thumb in the eye of the Washington establishment, Republicans very much included.

Mr. Blankenship offers no apology for his many contradictions and personal and business decisions, some of them previously undisclosed. Though he lives a baronial lifestyle thanks to a fortune built on coal scratched from West Virginia’s mountains, he says the size and origins of his wealth are no one’s business. He is the only candidate in either party in the Senate race who has not disclosed his personal finances as required by law to the Senate Select Committee on Ethics. There isn’t “much of a penalty” for flouting the law, he explained in an interview, justifying his refusal.

“I don’t personally think anybody should have to disclose private information,” he said while awaiting the start of a “meet the candidates” event last week in Cabin Creek, W.Va.