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Throughout the presidential campaign, Fox News will be breaking down the key issues and giving viewers an in-depth look at the positions of President Obama and presumptive GOP nominee Mitt Romney. This article in the AEHQ Issues series focuses on gay marriage.  

The Democratic National Committee made headlines this week with the announcement that for the first time, it is moving to include a plank supporting same-sex marriage in the party's convention platform.

It appeared to be a bit of an "in your face" to the host state, North Carolina, which just voted by 61 percent for a constitutional amendment to ban gay marriage.

The Democratic Party, though, has been emboldened since President Obama reversed course and came out in favor of same-sex marriage in May.

In the 2012 presidential race, both candidates are trying to appeal to their base on the issue. While Obama is the first sitting Democratic -- or Republican -- president to endorse gay marriage and in turn use that in his re-election race, Republican Mitt Romney's task may be to convince GOP voters he's firmly in the opposite camp on the issue. As governor of Massachusetts, he opposed gay marriage, but briefly entertained the idea of civil unions when the state courts ordered same-sex marriages to go ahead.

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Either way, gay marriage is arguably a bigger wedge in this year's presidential race than it ever has been thanks to the president's endorsement.

Obama has energized the LGBT lobby and Hollywood, raising millions of dollars off the announcement for his campaign.

"When the president came out in support of freedom to marry, he was doing what we elect presidents to do," said Evan Wolfson, president of Freedom to Marry.  "He was showing the moral leadership of standing up for the full protection and dignity of every American under the Constitution."

In embracing this wedge issue, though, Obama has not only contrasted himself with many conservatives, he has also managed to created deep divisions within his own party. On Tuesday, the Coalition of African-American Pastors launched a national campaign to withdraw support for Obama over same-sex marriage. Rev. William Owens, who is leading the campaign, complains that the President "threatens the stability of the family, especially the black family."

Owens said Obama has ignored the coalition's request for a meeting and today vowed, "We will see that the black community is informed that the president is taking them for granted while pandering to the gay community."

Such talk could be an indication that the president may run into difficulty in close swing states like North Carolina. "Key Democratic constituencies do not support same-sex marriage," said Brian Brown, president of the National Organization for Marriage.  "And I think that you are going to see a real lack of support for President Obama from them and then folks in the middle."

Romney may be angling for some of those votes. But while some conservatives are still anxious over where he actually stands, NOM's Brian Brown needs no convincing.

"If you go back to Massachusetts, people say no, no he wasn't strong on the issue", Brown told Fox News. "If you actually look at what he did, he stood up for a state constitutional amendment.  He fought so that the people could vote."

In Massachusetts, the issue never went to a vote.  In other states it did.  Twenty-nine currently have constitutional amendments banning gay marriage.  Many of those states, including North Carolina, also ban "marriage equivalents" like civil unions.

Four other states -- Washington, Minnesota, Maine and Maryland -- have put the question on the November ballot in some form.  Recent polls suggest that all of those states could vote in favor of same-sex marriage, which gives supporters reason to believe that the tide may be shifting in America.

"Republicans, too, are moving in the direction of support," Wolfson said.  "Young Republicans, like young Democrats, young independents, young people across the spectrum overwhelmingly support the freedom to marry."

It isn't just young people who are changing their minds. Longtime gay marriage opponent David Blankenhorn fought fiercely for Prop 8, California's measure to ban gay marriage. But in June, he wrote an op-ed in the New York Times with the headline: "How My View On Gay Marriage Changed". Blankenhorn is now fully in favor of same-sex marriage.

"As a marriage advocate," he told Fox News, "I feel that I can do more to strengthen the institution now by accepting gay marriage than by continuing to oppose it."  Blankenhorn says the public debate has come down to the question of whether the nation should support and recognize the dignity of homosexual love.  "And to me - the answer to that question is yes."

On the campaign trail, Romney doesn't talk much about the issue, leaving statements of "support for traditional marriage" to significant speeches like his appearances at Liberty University and the NAACP convention. Brown appreciates the support, though he wishes Romney -- and his fellow Republicans -- would talk more about it.

"There are plenty of Republican strategists in this town -- inside the Beltway that want to run from this issue. They think it is too divisive. They don't want to bring it up -- they don't want to talk about it," he told Fox News.

Brown is determined to make same-sex marriage a major issue in the fall campaign.  Ironically, it may be the split in the Democratic Party that fuels the debate more than anything Republican candidates are planning.

Editor's Note: An earlier version of this report identified David Blankenhorn as a conservative. He is a self-described liberal Democrat who was once opposed to same-sex marriage.