When Republican presidential candidate Michele Bachmann signed a pledge that claimed black Americans were better off as slaves than they are today, she apparently hadn't read it in detail.

Her campaign said Saturday that she actually didn't agree with that part of the pledge.

By signing the pledge created by Iowa-based Christian group The Family Leader, Bachmann agreed to opposes same sex marriage, oppose Sharia law and ban "all forms of pornography."

The "marriage vow" also begins by noting that the children of slaves were better off than African-American children 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 document (PDF) claimed.

But Bachmann campaign spokeswoman Alice Stewart said Saturday that the candidate didn't sign that part of the pledge.

"She signed the 'candidate vow,'" Stewart told Politico. "In no uncertain terms, Congresswoman Bachmann believes that slavery was horrible and economic enslavement is also horrible."

The campaign forwarded a note from The Family Leader to reporters Saturday.

"After careful deliberation and wise insight and input from valued colleagues we deeply respect, we agree that the statement referencing children born into slavery can be misconstrued," group spokeswoman Julie Summa wrote. "We sincerely apologize for any negative feelings this has caused, and have removed the language from the vow."

Republican presidential candidate Rick Santorum also signed the pledge before the slavery language was removed.

Santorum told CNN Sunday that he was "taken aback" by the pledge at first, but host Candy Crowley failed to ask him about the slavery claim.