I would say Donnie. He didn't freeze up when they almost lost. Where Raph froze up after Mikey got hurt. Donnie would be able to get out of a fight alive where Raph may not. After all, Donnie was the one to snap Raph back into reality after Mikey got hurt.

True but Raph is older and In epasods like a Foot to Big and the bigging of Spirit Quast he was in Charge of Training and he is also the one who lacturd Casey, Donnie and Miky that they always had to be prepard.

That is true. Raph is a good leader for training, but if Donnie, Mikey, or Leo got hurt, he would just freeze up like in New Girl In Town. Donnie seems to do better in battle, and if someone got hurt he would be able to lead them to safety.

Did't you see how he was Second in Command in the Follow the Leader epasod. He's obviously comming a long way as 2nd in command. Also if Donnie was better at leading then why is't he leading in training.

I forgot about that episode. And yes, he has come a LONG way since New Girl in Town. And also, Raph was considered, with Leo, the 'A-Team'. He could know how to fight better. Also, Raph was the oldest turtle when Leo was in a coma. 

Yes. Thank you.

During the episode "Follow the leader", Leo had has doubts about being the leader of the team.