Sorry, but this touched a nerve for me. The idea of blaming the stupidity of American voters on obesity is disturbing to me. Fat people get stigmatized too much already. (If that's not what you meant to imply, please accept my apologies for misunderstanding.)
If I'm reading right, this was one small study done on a cohort of only 175 subjects. In my opinion, that's not nearly enough data to be conclusive or upon which to base any assumptions about the cognitive functioning of fat people in general. Besides, I know far too many smart fat people who vote blue and far to many stupid skinny people to find this convincing. Anecdata, I know, but I can't discount it completely.
I'm sure you had absolutely no ill intentions in posting this, but I'm afraid that some could come away with an oversimplified impression that fat people in general are stupid, and I wanted to register my discomfort with that possibility.
In case anyone wonders, I am a formerly obese person who lost a large amount of weight with the help of bariatric surgery. I'm now at a healthy weight, neither clinically obese nor as thin as many would consider "ideal." I am also not one bit smarter now than I was when I was fat. I swear! 
(I know, more anecdata, but still.)
I apologize if I seem to be overeacting, but as I said, this touched a nerve. Even though I'm no longer obese, I still have a lot of feels about the stigma fat people live with and the way many people are quick to form negative judgments about someone who is fat without knowing anything else about them. Please feel free to ignore me if I seem to be going overboard. 
Peace out. ✌
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