www.thinkprogress.org/politics/2013/12/31/3108741/republicans-evolution-demographics/
"There are two keys to understanding what the Pew poll teaches us about Republicans. First, the drop in belief in evolution is among Republicans and, more or less, Republicans only. Acceptance of human evolution was basically the same among Democrats and independents in 2013 as it was in 2009. Second, the share of the total population that believes in evolution hasn’t changed at all. The drop in Republican belief doesn’t appear to be people changing their minds about evolution so much as people who already didn’t believe in evolution becoming Republicans.
Why might that be? The obvious explanation is the changing character of the Republican base."
