ABC News' Matthew Jaffe and Amy Bingham report:
Four GOP presidential candidates have refused to sign a controversial marriage pledge, which asks them to support outlawing pornography, upholding the Defense of Marriage Act and creating a constitutional amendment banning same-sex marriage.
GOP frontrunner Mitt Romney as well as fellow candidates Tim Pawlenty, Jon Huntsman and Newt Gingrich have not signed the Family Leader's Marriage Vow Pledge, but Michele Bachmann and Rick Santorum have.
Romney was the first GOP presidential candidate who refused to sign the pledge.
"Mitt Romney strongly supports traditional marriage but he felt this pledge contained references and provisions that were undignified and inappropriate for a presidential campaign," Romney's campaign said in a statement.
On the campaign trail in Iowa today, Tim Pawlenty announced his decision not to sign the pledge, and instead released a video discussing his personal faith.
Pawlenty's decision comes just weeks before the Ames straw poll which he desperately needs to do well in. Both Santorum and especially Bachmann pose real threats to Pawlenty in Iowa.
"Voters have a right to know about their leaders' faith and values, and how those beliefs may shape their decisions. To that end, today my campaign released a new video in which both Mary and I speak directly and openly about our faith," Pawlenty said in a statement. "I fully support traditional marriage. Unequivocally. The traditional family faces enormous challenges in America, and if elected I would vigorously oppose any effort to redefine marriage as anything other than between one man and one woman."
"I deeply respect, and share, Bob Vander Platts' commitment to promoting the sanctity of marriage, a culture of life, and the core principles of the Family Leader’s Marriage Vow Pledge," he continued. "However, rather than sign onto the words chosen by others, I prefer to choose my own words, especially seeking to show compassion to those who are in broken families through no fault of their own.
The Family Leader's choice of words for their Marriage Vow may not have been the wisest.
The Iowa-based conservative group retracted a portion of the pledge's introduction earlier this week that suggested African-American children were better off under slavery than they are today.
"Slavery had a disastrous impact on African-American families, yet sadly a child born into slavery in 1860 was more likely to be raised by his mother and father in a two-parent household than was an African-American baby born after the election of the USA’s first African-American President,” the statement read.
Both Bachmann and Santorum signed the pledge while the slavery comments were still intact.
The Pawlenty campaign is going to great lengths to promote his own words about faith and family.
He emailed his video to supporters along with a note from his Iowa senior political adviser Sarah Huckabee Sanders to Iowa voters and Huckabee supporters as well as statewide radio ads.
In the email, Huckabee Sanders compared Pawlenty's campaign — which has struggled in recent weeks — to her father's campaign four years ago, when he surprised the political world with a second-place finish in Ames and a first-place finish in the Iowa caucuses.
"At the time, he was low in the polls and didn’t have much money, but he won the Iowa Caucus because Iowans liked his executive experience, record of results governing a Democratic state, and conservative convictions," she said. "Today I’m back in Iowa working for Governor Pawlenty’s campaign because Governor Pawlenty has the same conservative convictions and executive experience I admire in my dad."
"Governor Pawlenty's commitment to faith and family is not a product of coaching by campaign consultants," she added. "As a devoted husband to Mary and supportive father to Anna and Mara, Governor Pawlenty gets it."