President Obama, former Vice President Al Gore and the United Nations, among others, argue that global warming is chiefly caused by human activity. A plurality of voters recognize that this view is held mostly by liberals rather than by all Americans.

In fact, a new Rasmussen Reports national telephone survey finds that 33% of Likely U.S. Voters mistakenly think most Americans agree that global warming is caused primarily by human activity. Forty-six percent (46%) recognize that the view is held primarily by liberals (To see survey question wording, click here.).

In a series of several separate surveys since August, roughly 40% of Likely Voters consistently have blamed global warming primarily on human activity. A plurality has just as consistently found that planetary trends are chiefly to blame.

Last April, 59% believed that there is a significant disagreement within the scientific community over global warming. Most (54%) voters believe the news media makes global warming appear worse than it really is.

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The survey of 1,000 Likely Voters was conducted on March 18-19, 2011 by Rasmussen Reports. The margin of sampling error is +/- 3 percentage points with a 95% level of confidence. Field work for all Rasmussen Reports surveys is conducted by Pulse Opinion Research, LLC. See methodology.