I think entj because he stammers a lot as he speaks publicly because he is trying to find the right words to not create a political firestorm many times. I think F types can "calculate" this quite easily subconsciously. He seems a lot more comfortable talking about ideas than social/political/feeling things. I think part of him despises that kind of politics because he views it as pandering to individual groups rather than doing what is best for all. I think people see him as F because of the focus on his eloquent speeches. In a speech he doesn't have to react in real time to others. When reporters grill him individually he sounds a lot more hesitant.