Poll Analysis: Clear Trend for Marriage Equality 

National support for marriage equality is not only growing but has accelerated significantly in recent years, according to a public opinion analysis by two pollsters -- one who worked for President George W. Bush, the other who serves as an adviser to President Barack Obama's reelection campaign.

Data from several national polling organizations, including Gallup and ABC News/Washington Post, this year indicated majority support for equal marriage rights, and such support has increased by 10 percentage points in the past two years, according to a memo published by Bush pollster Jan van Lohuizen of Voter Consumer Research and Joel Benenson of Benenson Strategy Group, who served as lead strategist in the 2008 Obama campaign and now works for the president's 2012 campaign. The memo was commissioned by Freedom to Marry, which presented the results Wednesday morning at the National Press Club in Washington, D.C.

"We're not in 1996 anymore," Freedom to Marry president Evan Wolfson said, referring to the year Congress passed the Defense of Marriage Act, which bars the federal government from recognizing the marriages of same-sex couples.

Speaking of the politically charged marriage issue in past elections, Wolfson said, "The wedge has lost its edge, and the third rail that people thought they saw actually appeals to groups of voters who are critical to winning campaigns."

Benenson and Van Lohuizen compared national polls over the past decade from Gallup, CNN/Opinion Research Corporation, and Pew Research Center, among others. "The remarkable surge over the last two years can't be explained by generational change alone," Van Lohuizen concluded. "It suggests that people across the political spectrum are rethinking their positions and deciding in favor of the freedom to marry."

A poll released earlier this week by Greenberg Quinlan Rosner and commissioned by the Human Rights Campaign also found a slim majority -- 51% -- in favor equal marriage rights for same-sex couples.

Not all recent surveys have found majority support, the two pollsters wrote in their analysis. A Quinnipiac University survey from earlier this month reported that 48% of respondents opposed marriage equality when asked specifically if they would support a law in their own state granting such rights to gay couples (46% approved).

Another, by the social conservative legal group Alliance Defense Fund, claimed that 62% of Americans said they supported marriage as only a union between a man and a woman in a June poll it commissioned.

"When you set it against these independent national polls, Gallup and others, who all have found something different, I think it says something about the wording and the methodology being as suspicious as the motives behind it," Wolfson said of the Alliance poll.

Benenson said in the press conference that while he does not advise clients -- such as the presidential reelection campaign -- on what positions to take, he said the marriage issue "has a very different calculus" in the current political climate than in past elections.

Whether that calculus, and trending public opinion, may resonate with the administration's reelection strategy as November 2012 nears remains unclear. President Obama has not indicated any personal shift on the issue in recent news conferences.

The Freedom to Marry memo tracks other estimates this year finding that a narrow majority of Americans support marriage equality with a small percentage still undecided.

Read the full memo via Freedom to Marry here.