Yet the 46th and 39th U.S. presidents had a decades-long friendship starting when Biden, as a young Delaware lawmaker, became the first sitting senator to endorse Carter’s outsider White House bid in 1976. Their bond will be on display one final time Thursday as Biden eulogizes Carter during his state funeral at Washington National Cathedral.

As a member of the elite, informal club of U.S. presidents past and present, Jimmy Carter was uniquely positioned to do important work for his successors, whether Democrat or Republican