Fifty-one percent of Americans oppose changing the 14th Amendment to prohibit "birthright" citizenship for the children of immigrants, according to a CNN/Opinion Research Corp. Poll released Wednesday.

Forty-nine percent, meanwhile, would support the change.

The issue came to the fore in early August when several GOP senators, including John McCain (Ariz.) and Mitch McConnell (Ky.), said they would support hearings to explore the issue as part of a larger move toward immigration reform.

In an interview that aired Wednesday, former Arkansas Gov. Mike Huckabee (R) notably came out against such a change.

"The Supreme Court has decided that, I think, in three different centuries," he said. "In every single instance, they have affirmed that if you are born in this country, you are considered to be a citizen."

The 14th Amendment, adopted in 1868, defines American citizenship as belonging to "all persons born or naturalized in the United States, and subject to the jurisdiction thereof." Critics say its automatic gift of citizenship to anyone born in the United States encourages illegal immigration.

Revising the amendment would require two-thirds of both houses of Congress and three-quarters of state legislatures to approve the new version.

The survey was conducted between Aug. 6-10 and has a 3 percent margin of eror.