"The study gives us more information to the point where the Pennsylvania House of Representatives is going to be out of excuses for not moving to action on closing the wage gap," she said.
A few statehouse Republicans have stepped out in front of women's issues legislation. They include Sen. Chuck McIlhinney of Bucks County, who is a co-chairman of the Women's Health Caucus, and Mr. Stephens, who sponsored a key bill in the package.
The Stephens bill would prohibit municipal nuisance ordinances that penalize domestic violence victims who repeatedly call 911.
The bill easily passed the House but stalled in the Senate because of a controversial amendment that would block municipalities enacting paid or unpaid leave policies.
"I'm not writing it off just yet. I think there's still an opportunity to get the underlying bill across the finish line," Mr. Stephens said.
Advocates for women's rights say that would be a good start, but there's much more work to be done at both the state and national levels.
Political scientists suggest the national tide may be turning ahead of the 2016 presidential election, particularly if Republicans want to avoid a repeat of 2012's 18-point gender gap.
They can frame the issues as pro-family and can more easily support pieces of legislation that have no or low cost.
"Creating time and space [for breast-feeding or expressing milk] might have some cost attached to it, but the cost is substantially different than providing weeks of paid maternity leave. So one possibility is negotiating what level of regulation [Republicans] are comfortable with in order to achieve a pro-family agenda," Ms. Lowe said.
Proponents, meanwhile, promise a sustained effort.
"We're looking at the long term. I know we're not going to have immediate passage ... but I do believe we will within the next five or 10 years," Ms. Arnet said.