No, because man needs grace and grace is obtained through Baptism. Grace restores us to the state where we are free to come to God. It was, indeed, impossible for anyone to come to God on his own until Christ's sacrifice on the Cross.
It is God who saves. But we must come to Him. He doesn't force us to sin and He doesn't force us to come to Him.
Prove positive of purely Pelagius' postulation.
Say that three times.
If grace is obtained through Baptism, then man is the one who can decide on God's grace. Man is the driver.