For the first time in history, a majority of Americans support gay marriage, according to a new poll.

A recent Washington Post/ABC News poll found that support for same-sex marriage has increased significantly in the last decade.

Backing of gay marriage has grown to 53 percent, while 44 were opposed, according to the survey (.pdf).

The data shows a trend of more and more Americans supporting same-sex marriage. In 2003, only 37 percent of Americans felt it was legal. Support grew to 47 percent by 2010.

While a majority of Democrats and independents supported gay marriage, only 31 percent of Republicans agreed with the idea.

All age groups saw big increases in support since 2005. Ages 30-39 saw a 23 point jump, the biggest among all age groups.

A recent Pew poll also observed an increase in those that thought same-sex marriage should be legal.

The poll found that 45 percent of adults surveyed favored allowing gays and lesbians to legally marry, compared to only 42 percent last year. Forty-six percent of those surveyed were opposed to same-sex marriage, a decline of 19 percent since 1996.

A 2010 Fox News/Opinion Dynamics poll found that 66 percent believed gays and lesbians deserved some form of legal recognition for same-sex marriages or civil unions.

Last month, President Barack Obama instructed the Department of Justice to stop defending a key section of the nation's laws banning gay marriage. Republicans in Congress vowed to fight the administration's decision.

-- with earlier reporting by Eric W. Dolan