Residing in Chicago , Mosteller assisted with the Obama presidential campaign at its inception in February 2007 . Working in Iowa , New Hampshire , and other pivotal states , he developed many of the policies and procedures used by the teams organizing the candidate 's travels and events . He was involved in the on-site organization of the 2008 primary debates and executed the senator 's role at the Democratic National Convention in Denver . Following Obama 's election , Mosteller moved to Washington , D.C. and started in the Oval Office hours after the inaugural . Mosteller was one of the longest serving staff members in the administration . Anonymous colleagues noted that " if you want a meeting at two in the morning , you go through him . " In a 2017 interview , Obama said of Mosteller , " He ’s a tireless manager and leader with a knack for sweating the small stuff . " In '' West Winging It '' , a memoir published in 2018 , the author references him as " responsible for maintaining dignity throughout the West Wing . " Mosteller is openly gay . On August 1 , 2016 , at his official residence , Vice President Joe Biden officiated at the wedding of Mosteller and Joe Mahshie , a member of First Lady Michelle Obama 's White House staff
Democratic National Convention
2008 Democratic National Convention
Brian Mosteller