Hartford Courant: The contrast could not be more striking: Every Democratic candidate for president has put forward an aggressive package of policies and statements on global warming and has made it a cornerstone of his or her campaign. Of the Republicans, just one, John McCain, comes close to matching the Democrats’ fervor for the issue. The GOP contenders focus instead on policies aimed at achieving energy independence – a goal that dates to the energy crisis of the 1970s. The contrast in this …