The US Conference of Catholic Bishops (USCCB) has issued a call for prayer and fasting for religious freedom on the Fridays of Advent this year.
From the USCCB website:
The U.S. Bishops are encouraging the faithful to pray and fast for the renewal of a culture of life and marriage and for protection of religious liberty. In particular, Catholics are invited to make a pledge to fast and abstain from meat on Fridays.