John McCainJohn McCainDrug importation won't save dollars or lives Dem rep Charlie Crist files for divorce Why the GOP cannot sweep its Milo scandal under the rug MORE's stance on climate change has proven to be controversial with at least one group of economic conservatives, as the Club for Growth today criticized the Arizona Republican's support for a cap-and-trade system.

The concept would set mandatory limits on greenhouse emissions, and allow companies that pollute less to sell their permits to those that pollute more.

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