Two Republican presidential candidates signed onto a socially conservative pledge pioneered by Iowa activist Bob Vander Plaats, his group said Friday.



Rep. Michele Bachmann (R-Minn.) and former Sen. Rick Santorum (R-Pa.) signed "The Marriage Vow," released Thursday by The Family Leader, the Iowa-based group headed by Vander Plaats.



The document is just the latest pledge for GOP presidential candidates, and focuses on a litany of social issues. Signatories, for instance, commit to fight against same-sex marriage, appoint conservative judges, and Reject Sharia Islam, among other items.



“We are thrilled that within 4 hours of its release, already two candidates have committed to The Marriage Vow and expect others to follow," said Vander Plaats. "Our goal is to send out The Marriage Vow to the candidates, including President Obama, by July 15th and have his/her signed document returned to us by August 1st. We can then publicize their responses at the Iowa State Fair and the Iowa Straw Poll.”



The Family Leader's leader has said he won't endorse any candidate who doesn't sign.

