Vivek Oberoi was signed for Arjun Rampal' s role but opted out.
The story draws parallels to the epic Mahabharata where shades of Arjuna (Kapoor), Karna (Devgn), Krishna (Patekar), Bhima (Rampal), Duryodhana (Bajpai), and Draupadi (Kaif) can be seen in the characters portrayed.
After the premiere of Rajneeti, Katrina Kaif touched Manoj Bajpayee's feet as a mark of respect for his role he essayed.
Although characters and their motivations are all inspired by Mahabharata, there are many scenes almost lifted from The Godfather (1972). The whole character of Ranbir Kapoor was inspired by Michael Corleone. Both were reluctant participants in the beginning but end up becoming key players in their respective family business. Both loses their wife/lover in a car blast planted by their enemies. The scene where Ranbir Kapoor goes to Manoj Bajpai's place to discuss about his family's safety and releasing his brother from Jail is identical to the scene in The Godfather when Vito Corleone assembles all the different Mafia families, infact the dialogue spoken by Kapoor is also a rephrased version of Don Corleone's speech. Another famous scene where Jack Woltz wakes up with the severed head of his prized stallion inspired the scene where Babulal wakes up with the dead body of his young male masseuse.
Sanjay Dutt had signed the film when Prakash Jha announced it in 2004. When the film got delayed Sanjay opted out.