Both players were instrumental figures in Los Blancos' title triumph last season, while the former Sevilla star also played alongside the Spain skipper as La Roja won Euro 2012 trophy this summer.
"I don't know what criteria are followed when voting for this award. The best thing would be to have a Golden Ball for each position on the field," the 26-year old stated to AS.
"How could I not hand the award to Casillas? There has only been one goalkeeper to win the award in the last 56 years. It takes many years to prove yourself the best in the world.
"But then, why not Cristiano? He is a player that makes a difference, and there is no one like him. I don't know the criteria, so I am not one to decide."
One high-profile player said to be close to leaving the Spanish capital is Kaka, and Ramos went on to say that his team-mate would always have the support of the dressing room.
"I haven't noticed anything about Ricardo [Kaka]'s attitude. He's a great player and demonstrates his professionalism every day. He has the support of everyone, no matter what the situation," Ramos commented.
The exit of the Brazilian playmaker is likely to be compensated by the purchase of Luka Modric from Tottenham, with the London side holding out for a €51 million deal, as Goal.com exclusively revealed.
"I've seen him. I like football, and I like good players. Modric is one of them, we faced him in the tournament [Euro 2012]. But for now he's not part of Real Madrid and I cannot say more."
Real Madrid kick begin their title defence on August 18, when they welcome Valencia to the Santiago Bernabeu.
||WHO WILL TOP THIS YEAR'S LIST?