Barcelona's advantage is that they can focus heavily on La Liga and the Copa Del Rey, while Real Madrid have set their sights on the Champions League and perhaps halfheartedly on the Copa Del Rey.
It's reasonable to think that Madrid will no longer focus on La Liga after trailing Barcelona by 12 points, but that doesn't mean they have to play badly and fail to win their other match. There is optimism on the part of Real Madrid, especially regarding the coach because in my opinion Ancelotti does not give up easily.
La Liga is their main focus right now in the midst of preparing for the Second Leg Semifinal against Real Madrid at Camp Nou.
However, it is also very natural that Barcelona focus on La Liga because there is no other competition that can be expected to lift a trophy other than the Copa Del Rey which they may not get because Real Madrid still has a chance to stop them.
Both Ancelotti and Xavi must have prepared several plans to anticipate that the team they are currently working with can get a trophy.
If Barcelona only has La Liga and the Copa Del Rey left, then Real Madrid still has the Champions League and the Copa Del Rey.
Between the two remaining competitions, who is the luckiest. That's what we are waiting for from the two coaches.