"Global warming was second to last among environmental issues. That is all you need to know," said Mike McKenna, a GOP pollster and consultant.
Poll: Half of Republicans back limits on carbon →
Mr. McKenna said Mr. Obama's executive order will shine a light on the ongoing schism between the GOP establishment and grass-roots conservatives over governance.
Obama amnesty: 2016 GOP hopefuls struggling to please base without angering Hispanics →