Rachel Posner's apartment number changes between episodes. It is 245 in this episode , but it was 246 in episode 21.
When President Walker accuses Frank (the current VP) of laying the ground work to challenge the him for the Presidency in 2016, Frank claims that "A Vice President has never challenged a sitting President." in hopes of dismissing the accusation. However, at least one time a sitting Vice President not only challenged his sitting President but also defeated his own President. Vice President Thomas Jefferson defeated incumbent President John Adams for re-election in the 1800 election. However, Frank and Walker could have been talking about the Democratic nomination while Jefferson was a Republican and Adams was a Federalist.
Dunbar tells Tusk that he has been accused of laundering Chinese money to "political super PACs" since 2005. Super PACs did not exist before 2010.