Congressman Tim Murphy, R-Pa., announced Wednesday that he will not seek re-election.

“After discussions with my family and staff, I have come to the decision that I will not seek reelection to Congress at the end of my current term,” Murphy said in a statement.

“I plan to spend my remaining months in office continuing my work as the national leader on mental health care reform, as well as issues affecting working families in southwestern Pennsylvania.”

Murphy faced a storm of criticism after the Pittsburgh Post-Gazette reported Tuesday on documents that suggested problems in his office and that he had urged a woman with whom he was having an extramarital relationship to get an abortion. Murphy has been a strongly anti-abortion politician.

The announcement comes four weeks after the congressman admitted to an extramarital affair with a psychologist he grew close with when she took on an activist role to help pass his bill to increased treatment availability for people with severe mental illness.

Murphy, who is married with an adult daughter, admitted to the affair after the Post-Gazette prevailed in a court motion to unseal a divorce case for which he was being deposed.

Murphy, 64, is not a party to the divorce but the husband in the case, sports medicine physician Jesse Sally, sought his deposition in July as part of his divorce from Shannon Edwards, who has acknowledged a six-month affair with the congressman last year.

Edwards, 32, has a doctoral degree and as part of her work evaluates defendants in criminal and child custody cases.

Murphy also is trained as a psychologist and has published books about children and anger. He served as a psychologist in the Navy Reserve until he retired in September.

At least three Democrats had already filed paperwork with the Federal Elections Commission disclosing their desire to challenge Murphy next year: former Allegheny County Councilman and teachers union official Mike Crossey, former Department of Veterans Affairs official Pam Iovino, and emergency physician Bob Solomon.

Already by Wednesday afternoon, one Republican, state Rep. Rick Saccone of Elizabeth, was openly expressing interest in the seat.

“What our congressman has done, if it’s true, has certainly disgraced the office. And if the people want me to take on that job, I would certainly look at trying to restore dignity back to the office.”

Saccone is currently seeking to challenge U.S. Sen. Bob Casey in next year’s Senate race. But he said he was watching developments close to home.

GOP sources in Pennsylvania say there is already movement toward state Sen. Guy Reschenthaler as a potential replacement for. Murphy, a resident of Upper St. Clair. Republican leaders see him as a good choice, sources said.

Murphy was first elected to Congress in 2002, after serving in Pennsylvania’s state Senate. His signature legislative achievement in Washington was the Helping Families in Mental Health Crisis Act, to which he devoted much of his 15 years in Congress. Said to be the most sweeping change in mental health policy in decades, his legislation was incorporated into the 21st Century Cures Act, which became law last year.

Speaker of the House Paul Ryan lauded the measure as a “landmark mental health reform” on Tuesday, just hours before news of Murphy’s text exchanges with Edwards came to light.

Murphy has also recently become involved in an investigation into the distribution of opioids by drug wholesalers. He had been helping to oversee the probe in his role as chairman of the Oversight and Investigations Subcommittee of the Energy and Commerce Committee.

Murphy also is chairman of the Congressional Steel Caucus, an informal group of lawmakers from steel-producing states.

A reliable party stalwart who blended labor-friendly positions on manufacturing with expertise in health, Murphy sailed through elections — often without a challenger — in a district that includes affluent suburbs with rural and white working-class communities.

But he hasn’t always been a favorite among his Republican colleagues in Washington, some of whom snubbed him in 2012 when they endorsed his primary challenger Evan Feinberg. Murphy defeated him by a margin of nearly two-to-one and went on to win the general election by nearly the same margin.

Murphy had faced controversy before. In 2006, he fired a staffer, Jayne O’Shaughnessy, who’d previously told the Post-Gazette that he improperly used congressional staff for campaign work. O’Shaughnessy said she was terminated 10 days after that story appeared. Murphy’s office, she told the Post-Gazette, was a “hostile environment.”

“If any little thing happened, if one little piece of information was missing from one part of his homework which wasn’t even worth talking about, he would just flip out,” she told the paper at the time.