WASHINGTON — As governor, Mitt Romney threatened one of Massachusetts’ dirtiest power plants to clean up or shut down, and he embarked upon a pioneering multistate pact to cut greenhouse gas emissions. He was hailed, at least initially, as an environmental champion. That was 2003.
By the time he accepted the Republican nomination for president in August, Romney had completed an about-face, reducing climate science — and President Obama’s efforts to fight global warming — to a punch line. Now, in the waning days of the campaign, Romney’s shift on what had been a backburner election issue could cost him some independent votes.