It’s not news that young people are more liberal on issues like same-sex marriage, but a new poll charts just how deeply that split has been carved into the white evangelical community, one of the most socially conservative groups on the American religious landscape.

The poll, released in late August by the Washington-based Public Religion Research Institute, found that nearly half (44 percent) of young evangelicals between the ages of 18 to 29 favor allowing gays and lesbians to marry.

By contrast, the white evangelical community as a whole (even counting those relatively liberal young adults) is solidly opposed to same-sex marriage, by slightly more than 80 percent.

More broadly, the poll found “at least a 20-point generation gap between millennials (age 18-29) and seniors (65 and over) on every public policy measure in the survey concerning rights for gay and lesbian people.”

The poll also found that a slight majority of all Catholics (52 percent) favor same-sex marriage, despite the energetic teaching of their church to the contrary.

The PRRI poll confirmed findings from other polls over the last five years that Americans have come to a tipping point on the issue of same-sex marriage: either equally divided (47 percent, according to the PRRI poll) or slightly in favor.

“This is the first year that support for allowing gay and lesbian couples to marry is not a minority position,” said Robert P. Jones, CEO of Public Religion Research Institute.

The survey of 3,000 U.S. adults has an overall margin of error of plus or minus 2 percentage points; the margin for young adult responses is plus or minus 4.5 percentage points.

Bruce Nolan writes for “The Times-Picayune” in New Orleans.