real madrid as other clubs in spain are registered as "football clubs" not PLC's or companies as in england and the president is elected by the club's members. the club cannot be sold as english clubs might since its a club "owned" by its members.
you can certainly however get elected a more adventurous president willing to offer you more budget; but it'll depend on how you perform on the field at the end of the day.
Barcelona, Real Madrid, Athletic and Osasuna all hold presidential elections. The remaining professional teams in the Spanish leagues are S.A.D. (Public Limited Sports Companies) in which the majority shareholder runs the club.
And of course due to the Real constitution you effecively have to be a tycoon before you can even run, as each candidate has to provide a guarantee of at least €57m to the club before they put their name forward. This is why Perez was unopposed in the last election. I read it in the Guardian but here is the official link.