Seven candidates had put themselves forward to lead the Partido Popular (PP) party nationally when nominations closed at 2pm on Wednesday.
Delegates will choose at a special conference on 20 and 21 July who will take over following the resignation of Mariano Rajoy after recently being ousted as prime minister. However before the conference convenes, all party members will vote on either their majority choice or the top two candidates, in a complicated voting system.
Three candidates are already emerging as favourites. Former deputy prime minister, Soraya Sáenz de Santamaría, and former party general secretary and minister for Defence, María Dolores de Cospedal, are seen as having the strongest chance, followed by Pablo Casado, party communication chief.