I dont quite know if this was posted before but who would Win in a battle explain why.
My opinion is Gaara. Neji relies on Close combat to win battles gaara is capable of using long range attacks. Think of it this way imagine Gaara blasting neji with long range sand waves, and Neji needing to use rotation as his only way to counter. Sure Neji would block it but Gaara can keep pounding him with sand. Gaara's Jutsu's are large scale look at the fight with kimimaru or whatever ( Bone Dude) Gaara pounded him with a giant wave of sand. Sure kimimaru lived but how can Neji keep on avoiding large scale attacks like that.
Another reason,Gaara's defense is more elaborate and stronger then neji's His shield of Shukaku jutsu is so powerful kimimaru couldnt break through it.