BOSTON (CNS) — The Boston-based organization Catholic Democrats asked pastors and parish administrators in a Pennsylvania congressional district to steer clear of partisan politicking prior to a March 13 special election.

A letter faxed four days before the election asked parish leaders in the 18th Congressional District to advise parishioners to form their consciences using guidelines established by the U.S. Conference of Catholic Bishops before voting.

The district includes Pittsburgh and parts of four counties in the heart of the nation’s steel industry.

Voters were to choose from Republican state Rep. Rick Saccone and Democrat Conor Lamb, a Marine veteran and former prosecutor, to fill the unexpired term of Rep. Tim Murphy, a Republican. Saccone, an Air Force veteran, was first elected to the state Legislature in 2010.

Murphy, who served eight terms in Congress, resigned in October after the Pittsburgh Post-Gazette reported that he had asked a woman with whom he had an affair to seek an abortion. Murphy had traditionally taken a pro-life stance throughout his legislative career.

The letter included links to USCCB documents including bulletin inserts discussing the quadrennial “Forming Consciences for Faithful Citizenship” and parish guidelines on what is and is not permissible prior to an election.

In addition, it called for instructions to be given to parish employees, ushers and others “to immediately removed unauthorized pamphlets and handouts within the church and on church property, including the parish parking lot.”

“Empower them to tell people leaf-letting cars on church property to leave immediately or the police will be notified,” the letter said.

The letter was signed by three members of the organization: Nick Cafardi, retired dean and professor of law at Duquesne University and a board member of the organization; Sister Patrice Hughes, a member of the Sisters of Charity and an educational consultant to the Diocese of Pittsburgh; and Kevin A. Hayes, with the group Social Justice Seekers.

President Donald Trump traveled to the district March 10 to rally for Saccone. Three days earlier, former Vice President Joe Biden was there to campaign for Lamb. While voting records indicate the district has 70,000 more registered Democrats than Republicans, Trump carried the district by 20 percentage points in 2016.

Political observers see the election as a key race leading to November’s midterm elections as Democrats seek to gain control of Congress.