Topeka ? Attorney General Paul Morrison acknowledged Sunday having an extramarital affair with a former staffer who now accuses him of sexual harassment and attempting to influence a federal case involving a political opponent.

Morrison said many of the claims made by the woman, Linda Carter, are “patently false.” She filed a civil rights claim last month with the federal Equal Employment Opportunity Commission.

Carter detailed her allegations in a signed statement obtained by The Topeka Capital-Journal, which published a story about them and Morrison’s acknowledgment of the affair in its Sunday editions. Morrison’s office issued a separate statement Sunday.

Her allegations and Morrison’s acknowledgment of the affair stunned the state’s political system and cast a cloud over Morrison’s future. Before the affair became public, even some Republicans assumed Morrison wouldn’t face a serious challenge if he sought re-election in 2010.

Carter is the former director of administration for the Johnson County district attorney’s office. Morrison was district attorney for 18 years before switching to the Democratic Party last year to successfully challenge GOP conservative Phill Kline for the attorney general’s job. Johnson County Republicans then picked Kline to take over Morrison’s old job.

During his successful campaign last year, Morrison faced allegations that he’d drunkenly propositioned another female employee in a bar in 1990. But two federal lawsuits arising from those claims were dismissed in 1992 and 1993, and the accusations backfired on Morrison’s opponents.

According to Carter, her affair with Morrison began in September 2005 and lasted for about two years, as Morrison ran for attorney general and after he took office. Her account said they had sexual encounters in the Johnson County Courthouse and hotels in several Kansas cities and three states.

She contends Morrison pressured her – unsuccessfully – to write letters for former employees who were dismissed by Kline after those employees filed a federal lawsuit. She also alleges Morrison sought sensitive information about Kline’s activities, including those related to abortion.

“Unfortunately, it is true, however, that I once had a consensual relationship with Mrs. Carter. And I profoundly regret that I did,” Morrison said in a statement. “Many of the details Mrs. Carter dished to the newspaper regarding the nature of our relationship are absolutely false.”

Kline spokesman Brian Burgess declined to comment, saying it would be premature because, “The situation is still developing.”