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Poll: 2 in 3 Democrats back same-sex marriage

SAN FRANCISCO, CA - JUNE 05: Bob Sodervick waves a gay pride flag outside of the Ninth U.S. Circuit Court of Appeals on June 5, 2012 in San Francisco, California. A federal appeals court announced that it will not rehear arguments on the California's controversial Prop 8 same-sex ban paving the way for the case to go to the U.S. Supreme Court. In February, a three-judge panel of the 9th U.S. Circuit Court of Appeals ruled that the same-sex marriage ban discriminated against gays and lesbians. Photo by Justin Sullivan/Getty Images

(CBS News) One day after national Democrats took a step toward include support for same-sex marriage on their official platform, a new survey from the Pew Forum suggests that most members of the party would support the move.

According to the poll, conducted from June 28-July 9 among 2,973 adults, nearly two in three Democrats - 65 percent - favor same-sex marriage.

It's an issue that many Democratic politicians have only recently embraced. Until this spring, President Obama characterized his views on same-sex marriage as "evolving" but declined to overtly support a law that would allow same-sex couples to marry.

In May, however, the president finished his evolution: In a hastily-arranged interview just days after Vice President Joe Biden talked openly about his support for same-sex marriage, Mr. Obama expressed his belief that "same sex couples should be able to get married."

The Pew survey suggests that Americans' beliefs surrounding same-sex marriage are also evolving over time. In 2004, only 40 percent of Democrats favored same-sex marriage; in 2008, that number had reached 50 percent.

Republicans and independents are less supportive of same-sex marriage, although those groups, too, have become more supportive over time. Currently, 24 percent of Republicans support same-sex marriage -- up from 19 percent in 2008 and 17 percent in 2004. Fifty-one percent of independents favor same-sex marriage, up from 44 percent in 2008 and 37 percent in 2004.

Overall, 48 percent of adults favor same-sex marriage and 44 percent oppose it, according to the poll.

The Pew survey suggests that there has been little shift in public opinion as a result of Mr. Obama's endorsement of same-sex marriage. Support for same-sex marriage in two Pew polls taken since the announcement are virtually identical from an April survey by the same organization.

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