Overall, not that much has changed in the religious make-up the United States legislative branch. While 95 percent of the members of the 87th congress that convened in 1961 were Christian, in today’s 115th congress that convened this week, 91 percent are Christian. Within Christianity, however, congress has become more Catholic, according to data provided by the Pew Research Center. The 87th congress is the earliest for which data is available.