The White House rolled out an official hashtag — #WHsurprise — for the event, and live-streamed President Obama, Michelle ObamaMichelle ObamaVideo surfaces of Michelle Obama at Beyonce’s birthday party Budowsky: Dems need council of war The Hill's 12:30 Report MORE and dog Bo greeting a long line of visitors in real time.

As the first couple greeted their guests, at least some of whom appeared to be former campaign volunteers that Obama thanked for their "hard work," the president demonstrated Bo on his best behavior. The Obamas' dog, whom Michelle Obama has called her "son," repeatedly obeyed the commander in chief's order to "sit."