Seven in ten young adults, those born after 1980, support gay marriage.

According to a Pew Research survey conducted in March and released on Monday, Millennial support for gay nuptials is 21 percent higher than the national average and far higher than in any other generation.

The poll found 49 percent support among Gen X-ers (those born between 1965 and 1980), 38 percent among Baby Boomers (1946-1964) and 31 percent among those in the Silent Generation (1928-1945). Overall, 49 percent of Americans favor marriage equality, while 44 remain opposed, according to the survey.

Ten states currently allow gay and lesbian couples to marry, the latest being Rhode Island, where a marriage bill signed into law Thursday takes effect August 1.

(Related: Gay groups cheer Rhode Island gay marriage; And a video, too.)

Opponents have previously dismissed the notion that overwhelming support from Millennials makes the expansion of marriage equality inevitable over time.

As recently as last week, Brian Brown, president of the National Organization for Marriage (NOM), suggested that young people would grow out of their support.

“But this idea that somehow young people's ideas are fixed and as they grow older they won't change their ideas is not true,” Brown told USA Today. “We believe all sorts of things when we were younger that we no longer believe.”