WILMINGTON, Del. (AP) — A former Delaware political candidate who unsuccessfully sought the Republican nominations for governor and U.S. Senate has pleaded guilty to federal charges of mailing threats to a lawyer who represented his wife in a divorce case.

Michael Protack pleaded guilty on Wednesday to two counts of mailing a threatening communication.

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Protack, 63, faces a maximum sentence of five years on each count at his Dec. 6 sentencing but will likely receive a lesser sentence. Prosecutors have agreed not to oppose a reduction in the offense level used in sentencing calculations based on his acceptance of responsibility.

Prosecutors say Protack, who now lives in Seal Beach, California, mailed two death threats to Delaware lawyer Patrick Boyer earlier this year.

An unsigned January letter was addressed to “Boyer. Little Boy,” with a return address of the “Viper Association” at a Wilmington post office box, according to investigators.

“The VIPERS are coming for you. We all have military experience and have no fear of the outcome,” the letter states. “You are a coward who will regret his actions. Count on being dead by June 2021. You won’t know when, where or how but your end has been written. Take the time and put your affairs in order because they will not find your body for weeks.”

Authorities said Protack followed up a few weeks later with a letter containing a graphic image of a mutilated body.

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Protack unsuccessfully sought the Republican nomination for governor in 2004 and 2008 and narrowly lost the GOP primary for U.S. Senate in 2006.

According to an FBI affidavit, Boyer began representing Mary Ann Protack in divorce proceedings in 2018 and helped her obtain “protection from abuse,” or PFA, orders against Protack.

“I could shoot you in the head and spend the rest of my life in jail happy about it,” Protack allegedly told his wife at one point. The affidavit added he also allegedly once told her, “Someone is going to die today.”

The divorce proceedings appear to have started around the same time that Protack, a former airline pilot who served in the Marine Corps, was notified that Delta Air Lines intended to terminate him. In a federal lawsuit filed in January 2018, Protack claimed that Delta had harassed and bullied him for years over his union activity and repeatedly questioned his physical and mental fitness after he was injured in a hit-and-run incident in 2012. The lawsuit also claims Delta unfairly portrayed Protack as “obstructionist” for refusing to submit to a psychiatric examination.

The case was dismissed early last year after being transferred from California to Georgia. Protack filed a similar lawsuit, without an attorney, earlier this year. That case was dismissed in late June because of Protack’s failure to properly serve the defendants.

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