Clark's conversation with Chloe about his fear that he might not be able to keep from hurting Lana during physical intimacy is a reference to a classic 1969 essay by science fiction author Larry Niven called "Man of Steel, Woman of Kleenex." In that article, Niven postulates that Superman/Clark Kent would be unable to have a sexual relationship with a non-superpowered woman, since his involuntary lack of physical control could result in catastrophic injury to his partner.
Lex tells Clark that asking him why the Senate seat is so important is "like Apollo asking Icarus why he's building wings". This is a reference to the Greek mythological story of Icarus. Imprisoned on an island with his father, they fashioned wings held together with wax to escape. Icarus' father cautioned him not to fly close to the sun, but Icarus ignored the warning. His wax wings melted and he fell to his death into the sea.
During the conversation between Lionel and Lex, there are quite a few quotes exchanged between them. The quotes were from the famous war book 'Art of War' by Sun Tzu, which happens to be Lex's present from Lionel when he turned fourteen.
Lex tells Clark jokingly that if he doesn't win, "There's always the White House." In the comics, Lex Luthor does indeed become President of the United States.
Lex looks to be in good health in this episode, despite being recently shot and having surgery to prevent paralysis in "Lexmas".