COLUMBIA, S.C. - A pair of Upstate House members have asked that their names be removed from a bill that would implement Gov. Mark Sanford's plan to give parents tax credits if they teach their children at home or send them to a private school.

Sanford sees the measure as enhancing school choice and creating competition that will make public schools better.

Reps. Garry Smith, R-Simpsonville, and Gene Pinson, R-Greenwood say too many questions are unanswered about the "Put Parents in Charge" legislation.

Smith says he is not sure how his name got on the bill. He questions "how we measure success and set up true market forces so parents can see apples to apples and make a comparison" of school options.

"I can't support it until we address these fundamentals," Smith said, adding that even with the answers "it's going to be a hard decision for me."

"You can't argue with the point of putting parents in charge," Pinson said. He wants to know how parents would select schools or whether those with learning disabilities will have sufficient choices. The bill doesn't deal with transportation issues for pupils with special needs.

Pinson, a former school board trustee, said Sanford doesn't have the answers to his questions. "I've tried to get them from him."

Sanford set the legislation as one of his top priorities. In his State of the State address last week, Sanford said it was "gut check" time and "for the state, and for the sake of these kids' lives, I ask for this bill's passage."

The House's two most powerful Republicans - Speaker David Wilkins of Greenville and budget committee chairman Bobby Harrell of Charleston - haven't signed onto the legislation.

"It's early in the process and there are a lot of questions being raised," Sanford spokesman Will Folks said. He expects that to change as a final version emerges. The defections of Smith and Pinson won't hurt the bill, he said.

"We're confident that when folks look at how successful school choice has been in other parts of the country, folks will come around," Folks said.

"Agents of the status quo" from within the education establishment, Folks said, are attempting to plant seeds of doubt among lawmakers to delay, water down or kill the plan.