The 2004 Spanish general election was held on March 14, 2004, following the Madrid train bombings that occurred just three days earlier. The election was called to select members of the Congreso de los Diputados and the Senate in Spain. The main political parties involved were the People's Party (PP), led by José María Aznar, and the Spanish Socialist Workers' Party (PSOE), led by José Luis Rodríguez Zapatero. The PSOE won the election, gaining a significant number of seats and marking a shift in Spain's political landscape.