Max Miller

A sordid, yearslong family drama involving two powerful Republican members of Congress from Ohio and allegations of domestic abuse is threatening to put a fairly safe G.O.P. House seat at risk in an already challenging midterm election year for the party.

Representative Max Miller, a second-term Republican representing northeast Ohio whose political rise was fueled by his close relationship to President Trump, has been accused by his ex-wife, Emily Moreno, of domestic abuse against her and their 2-year-old daughter.

Ms. Moreno, the daughter of Senator Bernie Moreno, also an Ohio Republican, has said that Mr. Miller scalded her chest and stomach by throwing hot water from a skillet at her body; held a gun to her head; pushed her against a wall and hit her head; and fractured their daughter’s collarbone and bruising her shoulder.

According to court documents, their daughter at one point told Ms. Moreno, “Daddy kill you.”

Mr. Miller has not only denied it all, he has gone on offense against Ms. Moreno, making damaging accusations of his own in a series of media interviews, court filings and countersuits that have kept the family’s personal trauma in the headlines. He has called his ex-wife mentally ill, a liar, a stalker and a dangerous individual who has made him and their daughter unsafe.

The legal and public relations war has in recent weeks risen to the level of a serious concern to Mr. Trump’s political operation, as well as White House officials, who are keenly aware that every seat matters as they stare down an electoral map that shows them at risk of losing their House majority.

They worry that Mr. Miller is harming his re-election chances and Republicans’ hopes of preserving the seat, according to three people familiar with internal discussions who spoke about them on the condition of anonymity.

Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.

Thank you for your patience while we verify access.

Already a subscriber? Log in.

Want all of The Times? Subscribe.