See a Sept. 29, 2006, Catholic News Service story, “What’s a voter to do? Election guides offer different answers” The CNS story focuses on Catholic groups but provides an overview of the issue.

“Preaching Politics from the Pulpit: 2012 Guide to IRS Rules on Political Advocacy by Religious Organizations” is a report released in October 2012 by the Pew Forum on Religion and Public Life, a project of the Pew Research Center.

“Voter’s Guide for Serious Catholics,” prepared by Catholic Answers Action.

Jan. 29, 2013, The Dallas Morning News blog post which takes offense to the belief that the religious left needs to be more combative to gain traction in the national conversation.

“Voting With a Clear Conscience” by the Rev. Frank Pavone, head of Priests for Life, a vocal group in the Catholic campaign to end legal abortion.

“The 2006 Elections: Becoming a Global Good Neighbor,” prepared by the Maryknoll Office for Global Concerns, which operates under the auspices of the worldwide order of Maryknoll priests, nuns, brothers and lay missioners.

Jan. 11, 2013, The Washington Post article on what the religious left must do to gain more national and media attention.

During the 2004 campaign, the National Conference of Catholic Bishops also issued a statement titled “Catholics in Political Life,” which sets out principles for Catholic candidates. On March 10, 2006, the bishops followed that up with a “Statement on Responsibilities of Catholics in Public Life.”

Transcript of an April 16, 2013, letter to President Barack Obama questioning the American drone program signed by several progressive religious leaders.