Though an unprecedented 50 percent of young adults described themselves as independent in the Pew survey, their beliefs by and large lean toward the Democratic Party. Tom Pennington/Getty Images

Half of Americans aged 18 to 33 are self-described political independents, but a similar proportion of so-called millennials acknowledge leaning toward the Democratic Party, a new survey suggests.

The percentage of respondents indicating an inclination to support the Democrats represents the highest share for any age group over the past decade, the Pew Research Center survey indicates.

In addition, young adults tend towards being increasingly single and churchless, researchers found. Almost two-thirds don't classify themselves as "a religious person," and only about 1 in 4 millennials is married. At that age, almost half of baby boomers were married.

The new survey shows how millennial adults are "forging a distinctive path into adulthood," said Paul Taylor, Pew's executive vice president and a co-author of the report.

This was especially pronounced in the realm of politics. Fifty percent of the millennials surveyed identify themselves as political independents – up from 38 percent in 2004 – while only 27 percent called themselves Democratic and 17 percent said Republican.

The number of self-described independents is lower among their predecessors. Only 39 percent of those in Generation X said they were independents, along with 37 percent of the boomers and 32 percent of the Silent Generation.

Pew describes Gen Xers as those of ages 34-49, boomers as 50-68 and the Silent Generation as those 69-86.

When the self-identified Democratic millennials combined with the self-described independents who lean Democratic, half of the millennials are Democrats or Democratic-leaning; 34 percent are Republicans or Republican-leaning, Pew said.

"They don't choose to identify, but they have strong views and their views are views that most people conventionally associate with the Democratic Party," Taylor said. "They believe in a big activist government on some of the social issues of the day – gay marriage, marijuana legalization, immigration. Their views are much more aligned with the Democratic Party."

Taylor said it isn't known whether the millennials' voting trends will stay the same as they get older.

"People can change over the course of their lifetimes," Taylor said. "At the same time, the behaviors, attitudes, the voting patterns and experiences that generations sort of encounter as they come of age in their late teens and early 20s are important, and this generation as political actors has come in three or four national elections in a row now as distinctively Democratic and liberal despite the fact they don't want to identify that way."

Millennials also haven't bought into the idea that they should go to church or get married early.

Only 36 percent of millennials said the phrase "a religious person" described them very well, compared with 52 percent of Gen Xers.

When they were the same age, almost half the Gen Xers – 47 percent – identified as religious. The 64 percent of the millennials who say that they are not religious is the highest for any age group Pew has ever surveyed.

The Pew study was based on interviews with 1,821 adults by phone in February.

The Associated Press