FACTBOX: presidential candidates on climate change

WASHINGTON (Reuters) - Here's what leading presidential candidates have said about climate change and energy policies, and what they want to do.

REPUBLICAN ARIZONA SEN. JOHN MCCAIN: "I know that climate change is real ... we've got to address it, we can do it with technology, with cap and trade, with capitalist and free enterprise motivation." Co-authored bill to cut emissions by 65 percent by 2050, favors unspecified fuel efficiency increase and overall energy efficiency.

DEMOCRATIC NEW YORK SEN. HILLARY CLINTON: "We need to start on a path to slow, stop and reverse the growth of greenhouse gas emissions." Supports an 80 percent reduction in carbon emissions by 2050, 40 mile-per-gallon fuel efficiency standard by 2017 and 10 percent cut in energy consumption by 2020.

DEMOCRATIC ILLINOIS SEN. BARACK OBAMA: "For the sake of our security, our economy, our jobs and our planet, the age of oil must end in our time." Supports 80 percent cut in carbon emissions by 2050, 50 mile-per-gallon fuel efficiency standard in 18 years and 50 percent cut in energy intensity -- the amount of power used as it relates to economic growth product -- by 2030.

(Reporting by Deborah Zabarenko, editing by Doina Chiacu and Vicki Allen)

(For more Reuters information on the environment, see blogs.reuters.com/environment/ )

(To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at blogs.reuters.com/trail08/)