(CNSNews.com) - As part of its ongoing efforts to ask policy-makers and public leaders the tough questions, Cybercast News Service asked the Democratic presidential candidates: "As president, would you support enacting a national carbon tax?" Following are the responses received. (Sens. Hillary Clinton, Barack Obama, Joe Biden, former Sen. John Edwards and Gov. Bill Richardson did not respond to requests for comment.)

Sen. Chris Dodd: "As President, Chris Dodd will institute tough, transparent, and effective 'cap-and-trade' rules that will make serious reductions in carbon emissions by the mid 21st century, begin to reverse the effects of global warming, and make America a global leader on the issue of climate change. [He would] enact a corporate carbon tax to discourage big corporate polluters and stimulate innovation. Revenues from the tax - estimated at approximately $50 billion annually - will be placed into a Corporate Carbon Tax Trust Fund to fund research, development and deployment of renewable technologies such as wind, solar, geothermal, as well as ethanol and other biofuels."

Sen. Mike Gravel: "Yes. Senator Gravel supports a carbon tax to encourage the adoption of cleaner energy solutions. Money generated from the tax would be used to fuel research into renewable and sustainable energy systems."

Rep. Dennis Kucinich: "We need to do whatever we can do to create disincentives for the use of carbon-based energy. But that's not enough. Carbon-based taxes alone won't cut it, because some people may be willing to pay an extra tax to use something that's bad for the environment. Inevitably we need a requirement to move away from all carbon-based technologies, and to fund fully all alternative-energy research that is in harmony with the environment."

(To read the question posed to the Republican presidential candidates, click here.)