John McCainJohn Sidney McCainMellman: Memories may be beautiful, yet… Schumer to oppose Pompeo as secretary of State Arizona GOP blocked from changing rules on filling McCain's seat 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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