Raul, who earlier this season become the leading scorer in Madrid’s history, struck in the 45th, 63rd and 66th minutes to continue his side’s amazing run of form under former Sevilla coach Juande Ramos.
Madrid pulled a little closer to Barca – who drew with Valencia on Saturday night – ahead of next weekend’s showdown at the Bernabeu.
Sevilla had threatened an upset when they went ahead through Renato Dirnei and then, after Raul had struck his quickfire treble, caused a few nerves when Diego Capel got the score back to 3-2 with 10 minutes to go.
However, Brazilian Marcelo broke away late on to slot home Madrid’s fourth.
It means Manuel Pellegrini’s side are just a point behind fourth-placed Valencia.
Villarreal looked to have had Sunday’s encounter all but sewn up by half-time after taking a two-goal lead thanks to Joan Capdevila and Joseba Llorente.
The visitors were reduced to 10 men when Angel Lopez was dismissed although a red card for Rafa Lopez evened up the numbers just two minutes later.
Manu del Moral gave Getafe hope by pulling a goal back late on, but it was not enough.
Athletic Bilbao are all but safe after a hard-fought 2-1 win over relegation rivals Racing Santander, but it was referee Gonzalez Vazquez who took centre stage as he doled out five red cards.
Spain striker Fernando Llorente score his side’s opener before earning a penalty which David Lopez converted four minutes from time.
Racing grabbed one back 10 minutes after the break through Pablo Pinillos from the spot.
As well as the five red cards, the referee also brandished a total of 17 yellow cards.
Mallorca all but secured Primera Division safety with an impressive 4-2 win at relegation-threatened Recreativo Huelva.
The islanders raced into a two-goal lead through Jose Manuel Jurado and Juan Arango.
Sisi pulled a goal back after the break, but Mallorca went two clear again through Gonzalo Castro 14 minutes from time.
There was another twist shortly afterwards when Javier Camunas bagged a second for the home side.
Alhassane Keita gave the islanders breathing space with an injury-time strike which sees them move up to ninth.
Sporting Gijon slipped into the relegation zone as they were defeated 3-1 by an unconvincing Atletico Madrid side at the Estadio Vicente Calderon.
After an uninspiring opening, Atletico took control with goals from Diego Forlan and Simao Sabrosa which put them two up at the break.
A goal for each side, from Atletico’s Sergio Aguero and Sporting’s Mate Bilic, within two minutes of the restart promised an exciting second period which never really arrived, though Simao did contrive to get himself sent off in the closing stages.
Osasuna are still looking anxiously over their shoulders at the relegation battle heating up below them after being held to the direst of goalless draws at Real Valladolid.
Espanyol moved out of the bottom three for the first time since mid-December following a 2-0 victory at home to Real Betis thanks to Luis Garcia and Roman Martinez.