New Hampshire has the highest estimated IQ in the country. That's why we have the primary.
The point to remember (other than that NH is all alone at 104): whenever you get one of those circulated internet things that tells you that Utah or somewhere has an average IQ of 86 or Connecticut 113, the numbers themselves are so implausible that you can reject them without reading further. There just isn't that much range. Average IQ's for any group, unless you are specifically selecting for something related to IQ, are going to hover around the national average of 100. In this instance, the "dumbest" states are South Carolina and Mississippi at 97. The difference between individuals with a 97 and a 104 IQ isn't that great. An average difference of 7 points is huge. When folks try to sell you average differences of 1SD (15-16 points), it's crap.
Related IQ post here.