A divisive plan to require photo identification for all Minnesota voters had an initial hearing Wednesday at the Legislature, but a state Senate committee delayed action on the proposal.

"I think it is a good idea to do whatever we can to protect the integrity of our voter system," said Sen. Scott Newman, R-Hutchinson, chief sponsor of the effort to put a proposed constitutional amendment on the 2012 ballot. It's among measures that GOP legislators are considering putting before voters in an effort to avoid the veto of DFL Gov. Mark Dayton, who rejected a voter ID bill last year.

In a standing-room-only hearing room Wednesday, a parade of speakers asked senators to stop the proposed amendment's march toward the ballot. After about five hours of testimony, the panel put off a vote on the measure.

Opponents said if the amendment were passed, elderly, disabled, homeless, minority and student voters would struggle to get proper documentation to allow them to vote. Requiring photo ID could add significant costs to election procedures and would effectively end Minnesota's long-standing system of vouching for fellow voters at the polls, speakers claimed. It could also put same-day voter registration and mail voting in jeopardy, opponents said.

"It is not a solution. It is a problem," said Kathy Bonnifield, executive director of the Minnesota-based Citizens for Election Integrity.

Supporters of the amendment said opponents had set up a series of "red herrings" to fight against the bill.

"It is almost like the testifiers think there are armies of ninjas" who would stop voters from getting the identification needed, said Dan McGrath, executive director of Minnesota Majority. McGrath said the simple requirement that residents present photographic identification before being allowed to vote would help ensure that Minnesotans cannot impersonate someone else at the polls.

"I don't have much faith in our system. ... We have the loosest voter system in the country," McGrath said. He dismissed the speakers at Wednesday's hearing as "a parade of professional activists."

Unlike the photo ID legislation that Dayton vetoed in 2011, the measure up for debate Wednesday did not define what identification would be required, whether voters' current address would need to be on the identification presented or how much the new requirement would cost. The constitutional amendment would require the state to provide free identification to eligible voters.

If the proposed amendment gets to the ballot and is approved, answering those questions "will be up to the future Legislature," Newman said. The measure would require lawmakers to figure out how to implement the amendment by July 30, 2013.

The only question in front of this year's Legislature would be whether to ask 2012 voters if the constitution should be amended "to require that all voters, at the time of voting, present valid photographic identification."

A proposed amendment that would effectively ban same-sex marriages is already on the 2012 ballot. Supporters and opponents have raised more than $2 million to campaign on that issue.

Although opinion polls show mixed results on whether voters want the marriage question answered in their constitution, polls clearly show voters like the idea of requiring photo ID at the polls. Minnesota is one of 19 states that allow voters to cast ballots without presenting any photo ID.

Rachel E. Stassen-Berger • Twitter: @rachelsb