Bernie Sanders, because he is a unique politician with some very strong ideas, he could change America in 4 or 8 years for the better.
I don't like any of the republicans particularly, but if I had to choose, Marco Rubio - he's the best informed and has the most consistent views.
As I said, the rest are jokes,
Donald Trump - never explains how he will accomplish things, if you turn a blind eye and ignore the racism and offensiveness, he has never explained 'how' he will get Mexico to pay for the wall, he has never explained 'how' he would defeat IS. His principles are simply that 'he's going to win', and Iowa proved that he isn't invulnerable and he isn't the most popular by far.
Ted Cruz - this man tried to shut down NASA's Earth associations because he doesn't believe in global warming. Someone who ignores every reputable scientist on the planet for no reason should not have this much power. He has also got a record of manipulation with the Ben Carson stuff.
Ben Carson - I'm not sure what this idiot is doing on the stage, he drones on about things and has very low enthusiasm, he quotes memes on the internet thinking that Stalin actually said something, he ignores climate change and he is just not fit for the job at all.
Jeb Bush - he's probably my second favourite just because he is polite and a reasonable person, but his campaign so far has been extremely inefficient.