The first Republican candidate to sign the list of demands issued by Iowa’s influential radical religious right group “The Family Leader” is, of course, Michele Bachmann: Update: Bachmann is first to sign Family Leader’s pro-marriage pledge.

The pledge is entitled, “The Marriage Vow – A Declaration of Dependence upon Marriage and Family.”

The organization’s chief executive officer is Bob Vander Plaats, a conservative evangelical leader who was the state chair of Mike Huckabee’s Republican presidential campaign when he won the 2008 Iowa Caucuses. Vander Plaats said the Family Leader will not support any candidate who declines to sign the pledge.

“If you are looking at being a leader of our great country….we would like to have you pledge personal fidelity to your own spouse and a respect for the marital bonds of others,” Vander Plaats told reporters at a news conference on the steps of the Iowa Statehouse.

U.S. Rep. Michele Bachmann, R-Minnesota, quickly signed the pledge Thursday, while an aide to to former Utah Gov. Jon Huntsman said he never signs any pledges. A spokesman for U.S. Rep. Ron Paul, R-Texas, said the congressman has reservations, while a representative of President Barack Obama’s Democratic campaign committee declined comment.

Former Minnesota Gov. Tim Pawlenty, a Republican, is reviewing the pledge, a spokesman said Thursday night. Several other GOP presidential candidates didn’t respond to requests for comment, including former Michigan Gov. Mitt Romney, former House Speaker Newt Gingrich, former Pennsylvania Sen. Rick Santorum, and retired Georgia businessman Herman Cain.

Presidential candidates who sign the pledge must agree to personal fidelity to his or her spouse, the appointment of “faithful constitutionalists” as judges, opposition to any redefinition of marriage, and prompt reform of uneconomic and anti-marriage aspects of welfare policy, tax policy and divorce law.

The Marriage Vow also outlines support for the legal advocacy for the federal Defense of Marriage Act, humane efforts to protect women and children, rejection of Sharia Islam, safeguards for all married and unmarried U.S. military service members, and commitment to downsizing government and the burden upon American families.

In addition, candidates are asked to recognize that “robust childrearing and reproduction is beneficial to U.S. demographic, economic, strategic and actuarial health and security.”