While Onorato steered away from the use of vouchers, Williams seemed untroubled by terminology, whether the idea was called grants, scholarships, or vouchers.
"The issue is having public money associated with a specific family that has a right to make a decision about where they send their child to receive a quality eduction," Williams said.
It appears that Onorato will not lose the backing of teachers, who support his broader education platform.
"Our view of him as a candidate has not changed. We believe that Dan Onorato is the best candidate for public education," said Wythe Keever, a spokesman for the Pennsylvania State Education Association. "We don't expect to agree with a candidate for governor all the time."
Keever said Onorato has told the union leadership from the beginning that he would take a "balanced approach to school choice."
Ted Kirsch, president of the American Federation of Teachers-Pennsylvania, said he would be part of an AFL-CIO meeting in Hershey Thursday at which Onorato would be endorsed.
"Although we may disagree with him on this issue, it's not going to be enough to not support him as a gubernatorial candidate," Kirsch said.