Dallas L. Toler, 45, entered his plea in U.S. District Court in Charleston and will be sentenced March 10. He faces up to five years in prison and a $500,000 fine.
Toler, who resigned as the county's chief magistrate in October, has agreed never to seek elected office again, the U.S. attorney's office said in a release.
"Corruption is the biggest threat to democracy," U.S. Attorney Booth Goodwin said. "In Mingo County, corruption was an epidemic. Once again in this investigation, we have a judge engaging in corruption -- this time corruption of the electoral process so that he and his cohorts could keep their jobs.
"The people of Mingo County are tired of these shenanigans, and we'll continue to do what's necessary to help them."
Toler was a candidate for magistrate and a member of a political fundraising and campaign organization known as Team Mingo, which advocated for Democratic candidates. In the spring of 2012, Toler arranged for a convicted felon who was living in one of his rental properties while on probation to vote in a primary election even though he knew the person was ineligible, federal authorities said.
Toler had been appointed magistrate earlier that year by county Circuit Judge Michael Thornsbury, 57, who pleaded guilty in October for taking part in a scheme to violate the constitutional rights of an individual to cover up evidence of illegal drug use and other misconduct by the late Mingo County Sheriff Eugene Crum.
Former Mingo County prosecuting attorney C. Michael Sparks, 44, pleaded guilty Nov. 18 for his role in a conspiracy to deprive a county resident of his constitutional rights.
Former Mingo County Commissioner David Baisden, 66, has pleaded guilty for taking part in a scheme to illegally extort a discount from a tire store.
Thornsbury, Sparks and Baisden, which West Virginia Metro News said were all members of Team Mingo, are awaiting sentencing.
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