Possible? Yes. As others said, love yourself first. Might be one of the hardest things to do in life, I don't love myself half the time, but if you can find some sort of inner peace, you'll gain a new level of confidence in the form of being comfortable with yourself. Losing weight might help you in that. Not saying you should, but there are many paths to feeling comfortable. That might be one. Plus, although I said it was possible, it is more unlikely, I think. People are attracted to what they are. Personality is important, but so is appearence. Overweight isn't attractive to most people, I imagine. Still possible for someone fat to get someone not fat, but it is tougher.
But to answer the question...I think it is 60/40. Confidence and personality and being comfortable is more important, but not by much. Looks are very important too.