DENVER (Reuters) - A Colorado talk radio host who once chaired the state Republican Party and has accused Democrats of widespread voter fraud has been charged with forging his ex-wife’s signature on a mail-in ballot in the 2016 election, court records showed on Wednesday.

FILE PHOTO - A man, wearing a hat with an embroidery of the U.S. flag, votes on election day at a polling station in Harlem, New York, U.S., November 8, 2016. REUTERS/Bria Webb/File Photo

Steven Curtis, 57, who served as state GOP boss from 1997 until 1999, is charged with one felony count of forgery and one misdemeanor count of tampering with a mail-in ballot, according to a criminal complaint filed in Weld County District Court.

The case stems from an inquiry lodged with the Weld County Clerk and Recorder’s Office by Curtis’s former spouse, Kelly Ireland, who contacted the agency in October to check on the status of her voter registration after the couple split.

Ireland was informed then that a signed mail-in ballot bearing her name and voter information had already been submitted, according to Carly Koppes, an elected Republican who serves as the county clerk.

“At that point, my office researched the situation further, and the signature was questionable, so we then contacted the District Attorney’s Office to start an investigation,” Koppes told Reuters.

If convicted, Curtis faces a maximum three years in prison for forgery and up to 18 months in jail and a $5,000 fine for ballot-tampering, said Tyler Hill, a spokesman for the district attorney.

Curtis’s lawyer, Christopher Gregory, declined comment.

The former Republican Party boss hosts a morning political talk show on conservative Denver radio station KLZ-AM called “Wake Up With Steve Curtis.”

Curtis spoke about election tampering in a segment titled “Voter Fraud and Other Democratic Misbehaviors” on his Oct. 6, 2016 broadcast.

“It seems to me, and correct me if I’m wrong, but virtually every case of voter fraud I can remember in my lifetime was committed by Democrats,” Cutis said, according to an archived podcast on the station’s website.

Prosecutors allege that weeks after that broadcast, he forged his ex-wife’s ballot.

A spokeswoman for Colorado Secretary of State Wayne Williams said the Curtis case is the only allegation of voter fraud in the state from the 2016 election cycle that has resulted in a prosecution.

Curtis on Tuesday made his first appearance in court, where he was advised of the charges. A disposition hearing has been set for May, the District Attorney’s Office said.

Republican President Donald Trump has claimed, without presenting evidence, that millions of illegal voters cast ballots in the 2016 election.