When the Alabama legislature passed a bill this year raising the cap, Governor Fob James vetoed it.

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Meanwhile, Governor Romney once supported a cap-and-trade mechanism to control carbon emissions but as the 2008 presidential race neared, he backed off and favored modest penalties for coal-fired power plants.

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He said he set up a per-capita cap in Missouri in 2002 and in 2001 Tennessee set up a per capita cap under a Democratic governor.

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