Michelle and Mark Schimel

Irreconcilable differences may explain why a separated Long Island couple are pitted against each other in a state assembly race.

Democrat Michelle Schimel, who currently represents the 16 th Assembly district and is running for her fourth term, will face her estranged husband Mark Schimel - once her suitor, but now her opponent - in the upcoming race this fall.

Married for 32 years, the Schimels have two children, but separated a year ago. They have yet to formally divorce.

Mark Schimel contacted the Nassau County GOP about seeking the Republican nomination to campaign for his wife's seat several months ago, and the county committee selected him for the Republican nomination last Thursday over two other candidates.

Frank Moroney, chairman of the North Hempstead Republican Committee, told ABC News Mark Schimel assured them he wasn't running with an agenda to hurt his estranged wife.

"He had the plan and the interest, and we made sure that everybody knows him. We weren't looking for a circus. We weren't looking for a sideshow," Moroney told ABC News. "We want an issue oriented campaign. He made that commitment, and we moved forward. He kept reassuring us that it was all about business."

Moroney said Mark Schimel was formerly a Republican, registered as a Democrat when his wife sought elected office, and recently returned to the Republican Party. Mark Schimel, who Moroney says is an information technology consultant and also is involved in the collection of rare coins, is currently assembling a campaign team.

"This is a very painful and personal family matter. The Republican Party is taking advantage of it and manipulating the political process. They are using it as an opportunity to drag my personal life into the public. This Assembly seat is a serious office. I will run this campaign as I have every campaign: on the issues, on my record, and on my values. I look forward to continuing to represent the people of New York State," Michelle Schimel said in a statement.

Scott Levinson, a campaign consultant to Michelle Schimel, saw the GOP nomination of her estranged husband to be a political stunt by the local Republican Party.

"We are going to the keep private life of the assembly member private. This is a personal matter," Levinson told ABC News. "The Republican party is clearly trying to manipulate this for their own political campaign.  The assembly woman is eager to return civility to her campaign and local politics, so she's going to remain committed."

ABC News was unable to reach Mark Schimel's campaign for comment.

Mark Schimel's mother, Irma, expressed disbelief at her son's decision to run against his wife to a New York paper.

"You're joking," Irma Schimel told the Daily News when she learned about his bid. "This is a really startling thing. It's a shock. Why would he do this?"

When contacted by ABC News, Irma Schimel said she was no longer discussing her son's campaign.