Murphy resigned last year after it was revealed that he had pressured Edwards to get an abortion during a pregnancy scare.
Edwards, who is a forensic psychologist, announced her candidacy at the steps of the Allegheny Courthouse, the Pittsburgh Post-Gazette reported.
“Pittsburgh deserves an active and diligent voice in Washington, D.C,” she said. “I will fight the tough battles that no one else chooses to fight.”
Edwards, who was an independent before registering as a Republican, said she is a moderate on social issues.
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“This is an entrenched Democratic district since 1953, and I hold values from both sides of the aisle,” she said. “In our current sociopolitical climate, people are used to checking a box — pro-life, pro-choice. I am pro-life span, not just pro-birth. I want to talk about health care.”
Her relationship with Murphy was revealed when her then-husband Jesse Kelly tried to have Murphy deposed in their divorce case.
“I don’t regret having the relationship,” she said. “We worked very closely on legislation that did a lot for my patients and clients. I can’t rewrite the past, and I don’t know what other course it could have gone.”
Edwards said she expects the affair to play a role in the campaign.
“I was warned. I have been given explanations. I have been told to back down, and I am here to tell you, nevertheless, I will endure,” she said.
So far, no other Republicans have challenged Doyle. After Pennsylvania’s new redistricting map, Doyle’s district is now the 18th District.