He let go his hope to become a human again and allowed Belle to return to her father. That is almost similar to Flynn's action.

He saved his love's father.
That is more than giving your life for you lover because he gave it up for someone he didn't know and was about to kill him, just for Pocahontas.
If he was willing to do this, he would be certenly willing to give up his life for Pocahontas.

I agree with LightningRed.

I think most if not all the princes would do this for their princesses. Each prince shows how in some way he would do this. If I only had to chose one though, it would be Beast. Beast lets Belle go when she was his only hope. He had learned to love and had to let go to do what was best for her even if it hurt him. When she returns he fights Gaston for her. He gets stabbed and dies because of it. So if it came to a situation where he had to die to save her life, I don't think he would hesitate.

I also agree with PociandSmith about John Smith. I can definetly see that he would sacrifice himself for Pocahontas.

or John Smith :)

LightningRed is right about John though.

He practically did with the wolves, and he gave up on life almost, which seemed he was sacrificing himself for love ( like " I would die for her")- then when he told her she could leave, even though he finally loved her more than anything.

Eric would be second cause he almost drowns trying to save Ariel in that storm that Ursula created.

He gave Belle her freedom so she could save her father and live happily again, promptly gave up on life as soon as she was gone, then didn't find the will to live until she came back. That's as good as giving his life for hers, just so she could be happy.

Or Phillip.