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The six lastest republic presidents over the last 50 years have a average IQ of 115,5.
President Nixon had the highest IQ (155) of them all.
President G. W. Bush has the lowest of all the republics with an IQ of 91.
http://www.personaltest.co.uk/iq/images/bush.jpg 
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The six democratic Presidents had an average IQ of 156,
President Clinton has the highest IQ: (182).
President Lyndon B. Johnson had the lowest IQ of all the democrats with an IQ of 126.
