When criticized for accepting money from energy companies, Hillary Clinton has protested that she makes her legislative decisions independent of campaign contributions. Experts differ on the influence of oil, nuclear and coal industries on presidents. Professor Gonzalez says that "any president will have to take their counsel to a certain extent."

According to author Tamminen, the oil industry contributed $186 million to congressional and presidential candidates during the past decade and received generous tax breaks in return, adding that "While it’s hard to prove any specific act of money-in-favors-out, those numbers speak for themselves."

Attorney Gold, however, says presidents act largely above the lobbyist fray. "I don't think people at that level are making decisions based on who gave them money."

Reviewing the Records

The three senators who are running for president have considerable differences in their environmental voting records, according to data from the League of Conservation Voters (LCV). According to the LCV scorecard, Obama had a perfect score during the 2006 congressional session (the last year that data was compiled), Clinton scored 71 percent, and McCain scored just 29 percent.

Despite Obama's stellar environmental voting record, he supports clean coal and nuclear technologies that are important to the economy of Illinois, but that some environmentalists find objectionable. In January of 2007, Obama co-sponsored the Coal-to-Liquid Fuel Promotion Act of 2007, which would provide funding to companies that convert coal to liquid diesel fuel. After taking heat on the bill, several months later Obama backtracked, saying he would only support clean coal initiatives that would reduce carbon emissions by 20 percent as compared with conventional fuels. He has also supported incentives for nuclear energy, including voting for the Energy Policy Act of 2005, which along with some funding for renewables gave tax breaks for expanding nuclear power.

Clinton has not authored any significant legislation concerning climate change or renewable energy. She has voted against coal to liquids as well as the 2005 Act that provided incentives for the nuclear industry. In 2007 she voted to expand offshore oil drilling.

McCain began sponsoring legislation to address climate change in 2003, before it became a popular subject in the senate. The "McCain-Lieberman" bill was also presented to the senate in 2005, but failed to pass. Like Clinton, McCain voted to expand offshore drilling, but unlike his two peers, he was not present to vote for the landmark 2007 energy bill that raised vehicle fuel economy standards.

Both governors took measures to address climate change during their administrations. As governor of Arkansas, Huckabee adopted the National Governors Association's 2006 policy position on climate change, promoted energy efficiency by switching to compact fluorescent lighting, and signed into law the Arkansas Renewable Energy Development Act.

As governor of Massachusetts, Romney promoted a Climate Protection Plan, which encouraged required state agencies and large businesses to reduce carbon dioxide emissions. He also supported an agreement of northeastern states to reduce greenhouse gas emissions. Neither governor did much while in office to encourage the development of clean technology, however.

Whoever takes office in 2008 will have to prioritize energy and environmental concerns among many other issues and work closely with Congress to enact new laws. Attorney Gold says that with a slipping economy, climate change legislation may have to take a back seat. Working with Congress during the "honeymoon days" that coincide with a new administration, however, might be the best time to get green legislation passed, according to Gold.

Professor Gonzalez says the increased talk of clean energy and climate concerns on the campaign trail could result in new executive action. "I have more hope that someone who is talking about it more will take action (in the White House)."