The so-called birther bill won initial approval from the state House on Monday, advancing legislation that would require presidential candidates to produce a birth certificate before they can be on the ballot in Arizona.

The bill originated from a group that believes President Barack Obama is not a natural-born citizen of the U.S. and is ineligible to be president.

Rep. Judy Burges amended Senate Bill 1024 to include a requirement that Arizona's secretary of state inspect a presidential candidate's birth certificate before that candidate could qualify for the ballot.

Similar laws have been proposed in Oklahoma, Florida and Missouri. None has been signed into law.

Democrats criticized Burges' amendment, saying presidential candidates already have to prove their citizenship.

"Republicans continue to take Arizona down the wrong track by wasting taxpayers' time on frivolous legislation instead of working on important issues like health care for kids and seniors and education," said Rep. Kyrsten Sinema, D-Phoenix.

Burges, a Skull Valley Republican, did not respond to a call for comment.

Arizona Secretary of State Ken Bennett said creating state-level requirements for a federal office could violate the U.S. Constitution.

"While everyone has an interest in ensuring that only eligible citizens run for president, there are obvious issues with states implementing what could become a patchwork of different tests for a presidential candidate to prove his/her citizenship," Bennett's spokesman, Matthew Benson, wrote in an e-mail.

The amended bill still needs final approval from the House and will require another vote in the Senate before it can be transmitted to Gov. Jan Brewer.