Ainsley tries to get a can of Fresca, but they do not keep Fresca in the building. According to historian Doris Kearns Goodwin, Lyndon Johnson loved the soda Fresca so much he had a fountain installed in the Oval Office that dispensed the beverage, which the president could operate by pushing a button on his desk chair.
The gay Republican Congressman may be an acknowledgment of the real organisation called the Log Cabin Republicans. It is for gay Republicans to lobby for gay rights within the party.
The President (Martin Sheen) claims that Zedong Mao took a lot of long flights. Actually, he never flew, as travelling by plane would leave him vulnerable to assassination attempts. He preferred using an armoured train.
The phrase 'permanent revolution' is most closely associated with Lev Trotskiy, not Zedong Mao, as Toby (Richard Schiff) and the President (Martin Sheen) claim.
When Charlie (Dulé Hill) hands C.J. (Allison Janney) the lyrics of the "Notre Dame fight song", Jed (Martin Sheen) tells C.J. she will lead the press corps in singing all five verses. The Notre Dame Victory March has only two verses and a chorus. The two verses are sung together, though they are often omitted and the chorus is sung alone. Jed is likely having a joke at C.J.'s expense, and the lyric sheet contains the two verses.