Lee had smaller forces and took larger losses than McClellan in those battles.
That was probably inevitable: to win battles generals sacrificed troops.
But the idea that Grant was the butcher or the plodder who only won by taking higher losses and Lee the surgeon who could win campaigns through genius, rather than loss of life, is revealed to be false by those 1862 battles outside Richmond.
Lee had McClellan so fooled about his troop strength and precise location that it made him hesitate to commit the vast majority of his forces to engagement. I give him a lot of credit for that.
Either Mac was drunk or totally paranoid. He could have and should have won the vast majority of those engagements.
Grant did what Mac should have done, committed his full forces and used his cavalry to confuse.