The Pew Research Center for the People and the Press in a telephone interview received a positive response from 66 percent of adults asked about the Keystone XL pipeline.
Canadian pipeline company TransCanada wants to build the pipeline to carry oil from tar sands projects in Canada to refiners along the southern U.S. coast.
More than 80 percent of the people who identified themselves as Republicans expressed support for the project compared to 49 percent of the people who said they were Democrats. More than 60 percent of those who said they were independents said they backed the project.
Backers of the pipeline say it's a "shovel-ready" project that would boost employment and enhance U.S. energy security. Critics question the job numbers given as evidence to back the pipeline and note tar sands oil is the dirtiest type of crude oil.
Of the 1,501 adults surveyed in the mid-February poll, 37 percent of the respondents said they've never heard of Keystone XL compared to 24 percent who said they heard a lot about the issue. The rest said they knew a little bit about Keystone XL.
Overall, the poll reported a sampling error of 3 percentage points.