WILLIAMSPORT, Pa. — Amber Hamilton had scathing words for her congressman, Representative Tom Marino, after learning he had championed a law that critics say makes it easier for opioids to enter the black market.

“Does he even care about his people?” said Ms. Hamilton, 37. Like Mr. Marino, she is a native of Williamsport, a small city in central Pennsylvania that is best known as the birthplace of Little League baseball, but that is now confronting an opioid blight running deeply and broadly through its picturesque valleys.

For Ms. Hamilton, like many others here, the issue is both stark and personal. A mother of two and a recovering addict, she got hooked on pain pills after surgery more than a decade ago, then turned to heroin. “I don’t want my kids to have the life I have,” she said after leaving a clinic near the bus terminal, where she picks up medicine to stave off cravings. “And I want a politician, whoever is going to be in charge and represent Williamsport, to care about the community and want to make it better, not worse.”

Mr. Marino, a Republican, withdrew as President Trump’s nominee for drug czar on Tuesday after news reports that the pharmaceutical industry contributed close to $100,000 to his campaign while he shepherded a law making opioids more easily available in the midst of a national crisis.