The former chairman of the GOP in Colorado was found guilty of voter fraud Thursday after prosecutors say he filled out and mailed in his ex-wife’s ballot.

Steve Curtis will be sentenced in January and could face up to three years in prison, the Weld County District Attorney’s Office said in a news release.

The 58-year-old was charged in February after DNA evidence and handwriting analysis linked him to his ex-wife’s ballot.

This came after Curtis’ ex-wife – who had not lived with him in nearly a year – called the Weld County Clerk and Recorder’s Office in October 2016 to obtain her mail-in ballot. That’s when she was told that she had already voted, even though she hadn’t.

During the trial, the DA’s office says Curtis testified that he signed the ballot in the middle of the night while suffering a diabetic episode.

RELATED: Former Colorado GOP chair pleads not guilty to voting fraud

This was a claim disputed by prosecutors during closing arguments.

“He knew exactly what he was doing,” Deputy District Attorney Tate Costin said. “He received it in the mail, opened it, voted, signed it, and sealed it back up and sent it in. If he were going to sign a name during this confused diabetic state, wouldn’t he sign his own name? Why her name? She hadn’t even lived in the house for 11 months.”

Curtis served as the chairman of the Colorado Republican Party from 1997-99, and he since has worked as a talk show host on the radio station KLZ-AM 560 in Denver.