From the Pew Research Center:
A 53%-majority of Republicans say there is no solid evidence the earth is warming. Among Tea Party Republicans, fully 70% say there is no evidence. Disbelief in global warming in the GOP is a recent occurrence. Just a few years ago, in 2007, a 62%-majority of Republicans said there is solid evidence of global warming, while less than a third (31%) said there is no solid evidence. Currently, just 38% of Republicans say there is solid evidence the earth is warming, and only 16% say that warming is caused by human activity.
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