A Democratic super PAC is meddling in West Virginia’s Republican Senate primary to boost Don Blankenship, an energy executive convicted of conspiracy to violate mine safety standards who is viewed as the weakest challenger to incumbent Sen. Joe Manchin, D-W.Va.

Duty and Country has filed independent expenditure reports with the Federal Election Commission for hundreds of thousands of dollars in advertising opposing Rep. Evan Jenkins and state Attorney General Patrick Morrisey. The two Republicans are considered tougher for Manchin to beat in November than Blankenship, who went to prison in 2016 after being found negligent in the deaths of 29 coal miners.