["Journal for the Scientific Study of Religion, EarlyView. ", "\nAbstract\nWe use data from the National Congregations Study (NCS), including data from the fourth wave, to describe congregations’ political activity in 2018–2019, and to examine change in that activity since 1998. Congregations have become more politically mobilized since 1998, with the majority of congregations (56 percent) engaged in at least one of the political activities asked about in 2018–2019. Black Protestant congregations in particular experienced a surge in political activity since 2012, and congregations with politically liberal convictions or in traditions with more immigrant members have substantially increased their advocacy on behalf of immigrants in recent years. Overall, since 2012 and possibly since 1998, the political mobilization of congregations on the left has increased more than political mobilization of congregations on the right. We also find that 4 percent of (overwhelmingly Catholic) congregations have declared themselves sanctuaries for undocumented immigrants, and a surprisingly large minority (17 percent) of congregations would publicly endorse or oppose political candidates if doing so would not put their tax status at risk. Ironically, in light of the support for this tax law change among conservative leaders, African American and politically liberal congregations are by far most likely to publicly endorse a candidate if they could.\n"]