Real are probably full of confidence because of the Liverpool result. But Barca will also be full of confidence, they just haven't been dropping any points in the league at all, it's win after win after win.
It will probably be a tight match with both teams scared to lose... but at the same time, a draw isn't that good for either of them. Might just need a moment of Messi magic to open the game up.
The good part is, whatever the result will be, it is going to work for ATM at least, a tie would be best option for them but even if Barcelona wins which is the worst deal for ATM right now, that means at least the second spot will be more easy for them, but they have to stop losing to lower end teams in order to keep their fighting chance. I believe Barcelona will win, they do not have champions league, they do not have anything to fight for aside from the league.
Real Madrid just won against Liverpool and even though they may feel good about themselves and that could result with morale during Barcelona game that is still not enough to beat Barcelona. Barcelona has something much more important, a chip on their shoulders and that should be giving them a lot more fire to win this game than real would ever have at the current stage which is why I wagered on Barca to win.