One-in-three voters think the United States has stepped up its exploration of alternative energy sources, a significant improvement from previous years.

The latest Rasmussen Reports national telephone and online survey finds that 33% of Likely U.S. Voters believe the United States is doing enough to explore alternative sources of energy, up from 17% in 2014 and 18% in 2013. Fifty-two percent (52%) disagree, while 14% are not sure. (To see survey question wording, click here.)

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The survey of 1,000 Likely Voters was conducted on June 3-4, 2018 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.