From CNN
DES MOINES, Iowa -- Former Massachusetts Gov. Mitt Romney's campaign said Tuesday that he will not sign a conservative Iowa Christian group's far-reaching pledge opposing gay marriage, making him the first Republican presidential candidate to reject it.

Two of Romney's rivals for the Republican nomination, Minnesota Rep. Michelle Bachmann and former Pennsylvania Sen. Rick Santorum, have signed the The Family Leader's 14-point pledge, which calls on the candidates to denounce same-sex marriage rights, pornography, same-sex military accommodations and forms of Islamic law.

When it was first circulated last week, the introduction to the pledge stated that African American children were more likely to be raised in two-parent households when they were born into slavery than they are today. The group struck that language and apologized after black ministers complained, but it said it stands by the rest of the document.

Andrea Saul, a spokeswoman for Romney, told The Associated Press in a written statement Tuesday that Romney "strongly supports traditional marriage," but that the oath "contained references and provisions that were undignified and inappropriate for a presidential campaign."

Bachmann and Santorum have been campaigning hard to court the influential social conservatives in Iowa, which holds the nation's first caucuses. Romney's rejection of the pledge reflects his diminished focus on winning Iowa, where he spent $10 million during his 2008 presidential campaign only to finish second.

None of the other GOP presidential hopefuls, including former Minnesota Gov. Tim Pawlenty and former U.S. House Speaker Newt Gingrich, have said whether they will sign the pledge or not.

Romney, who supported rights for gay couples in Massachusetts, was criticized in Iowa by some Iowa social conservatives during his 2008 campaign, when he finished second in the caucuses after aggressively courting Christian conservatives.

In his second bid, Romney, who leads in national GOP polls, has cast himself as a national figure more focused on the economy, and has said he would not spend as much time and money campaigning in Iowa as he did during his $10 million effort for the 2008 caucuses.

The Family Leader, an organization formed last year and positioning itself to be an influential player in the 2012 caucuses, said Tuesday they stand by the 14 policy positions listed under the promise to "defend and to uphold the institution of marriage as only between one man and one woman."