With even President Bush recently announcing a national goal of stopping the growth of greenhouse gas emissions in the U.S. by 2025, it's clear that the environment isn't merely an election year issue used by the 2008 presidential candidates to pluck green heartstrings in an effort to gain votes. Both contenders acknowledge the dangers of climate change, our dependency on foreign oil, and carbon emissions; and each has made serious environmental policy promises. Here's how the candidates measure up—to their touted eco-awareness as well as to one another. BARACK OBAMA Enviro stance in one word: Morality Obama and Clinton have almost identical environmental platforms. Both support a cap-and-trade method of reducing carbon emissions 80% below 1990 levels by 2050. Both want to derive 25% of the nation's electricity from renewable sources by 2025, and both call for Americans to use 60 billion gallons of biofuels per year by 2030. And both candidates balk at nuclear energy, saying that problems with cost, waste, and proliferation must be solved. Obama's plan diverges in a few key ways. His environmental solutions stress the moral necessity of addressing our country's—and the world's—environmental problems. He says he'll invest $150 billion over a decade in the research and development of clean, renewable fuels, technologies, and infrastructure—then make them available globally. His fuel-economy standards focus on 2020 as a deadline for cars to reach 40 miles per gallon. He wants the federal government to source 30% of its electricity from renewable sources by 2020, and phase out the use of incandescent light bulbs by 2014. (Obama's plan.) League of Conservation Voters lifetime score: 86% Does he walk the talk? Positive: While in college, he worked for an organization affiliated with Ralph Nader promoting recycling efforts among minority students at City College in Harlem. Negative: Obama chose not to support a mining reform bill that would have modernized the Mining Law of 1872, which levies few to no royalties for private companies to mine public lands. JOHN MCCAIN Environmental stance in one word: Stewardship McCain echoes the Democrats' stance on the need to reduce carbon emissions, and he supports a market-based cap-and-trade system. His targets differ a bit: He wants to lower carbon emissions 65%, not 80%, by 2050. His plan for promoting renewable electricity focuses on state and local rather than federal government responsibility for setting standards; he therefore sets no timelines or limits. McCain's supportive positions in other areas of environmental concern also lack defined timelines or goals. He wants to eliminate ethanol subsidies and develop sources for ethanol other than corn. His congressional record includes cosponsoring and supporting various environmentally forward bills, such as his cosponsoring of the Climate Stewardship and Innovation Act of 2007 that contains funding for nuclear energy research, which McCain strongly supports. (McCain's plan.) League of Conservation Voters lifetime score: 24% (0%for 2008, since he's missed all key votes on environmental legislation so far this year) Does he walk the talk? Positive: In 2003, McCain cosponsored the first bill addressing carbon emissions with a cap-and-trade system. Negative: He has called for a national gas tax holiday for the summer, which would eliminate gas and diesel taxes for three months. He and his wife, Cindy, reportedly own at least eight homes.