HARRISBURG — Republican state senators from the Philadelphia region have emerged as an unexpected but critical group in deciding  the fate of a controversial measure that would temporarily allow older victims of alleged child sexual abuse to sue their abusers and the institutions that covered up for them.

Three of the lawmakers are moderates from Bucks, Delaware and Montgomery Counties who face tough races in next month's election, projected to draw Democratic voters opposed to President Trump. Two others are retiring, and their votes are likely to be among their final acts as legislators.

Lobbyists on both sides of the debate are eyeing the group — and activists are expected to increase the pressure, including through protests, as the election nears.

"This is a critical vote — and we are counting on that region for support," said Shaun Dougherty, who said he was sexually abused by a priest when he was a boy and who has spent weeks trying to win votes for the bill.

The measure would, among other changes, suspend for two years the civil statute of limitations for child sex-abuse offenses so that people who were sexually abused decades ago as children can file lawsuits. Under current law, victims have until age 30 to sue.

The fight over the two-year window has been fueled by the release in August of the statewide grand jury report on Catholic clergy sexual abuse. The report detailed seven decades worth of abuse by more than 300 priests statewide, and painted a blistering picture of church officials routinely covering up the crimes until they were too old to prosecute or litigate. In their report, the grand jurors called for suspending the statute of limitations to allow victims to seek justice.

The Republican-controlled House of Representatives last month easily passed a bill that includes a two-year window – and Gov. Wolf supports it. But its fate in the GOP-controlled Senate, where half the seats are up for grabs next month, is unclear. A vote is expected this month.

The Senate currently has 33 Republicans, 16 Democrats, and one vacant seat. Senate Democrats say most of their members have committed to backing a two-year window, which means it will need at least nine Republican votes to pass.

Senate President Pro Tempore Joe Scarnati (R., Jefferson), who has significant influence over his party's rank-and-file members, has opposed the measure, arguing any retroactive change in the statute of limitations is unconstitutional. Senate Majority Leader Jake Corman (R., Centre) — who also is up for reelection and whose vote has become a campaign issue — has kept quiet about his position, but provided a glimpse late last month when he stood next to Scarnati to detail what he called "glaring problems" with the measure approved by the House.

Still, some GOP senators have signaled they would break with leaders. Sen. John Rafferty (R., Montgomery) has for years said he would vote to suspend the statute of limitations. Sen. Thomas Killion (R., Delaware) said this week that he too would vote for a two-year window, if it comes to the floor for a vote.

Sen. Stewart Greenleaf (R., Montgomery) is retiring after four decades. He said last week that he will recuse himself from the vote, just as he did when a similar measure collapsed in 2016, because his law firm once represented a religious order fighting a similar law in Delaware.

The other retiree, Sen. Charles McIlhinney (R., Bucks), is less conflicted. Last week, he said opening a window is unconstitutional. He also said he thinks the measure is being pushed by trial lawyers motivated by making money off future suits. "Half that money would end up in a lawyer's pocket," he said.

Much of the focus has fallen on three area Republicans running for reelection.

Sen. Thomas McGarrigle is a Delaware County incumbent locked in a heated race with Democrat Tim Kearney, the mayor of Swarthmore. McGarrigle said last week that if the two-year window were brought to a floor vote, he would support it.

Sen. Bob Mensch of Montgomery County said he has not made up his mind. Mensch, up against Democratic challenger Linda Fields, said he is concerned about language in the current bill that would require people suing public institutions, as opposed to private ones, to meet a higher standard of proof.

Sen. Tommy Tomlinson is a longtime Bucks incumbent facing a stiff challenge from Democratic State Rep. Tina Davis. Tomlinson has not made his vote known. He did not return multiple calls, and when approached in a Capitol hallway last week for an interview, he said only: "Later."

Another Republican senator facing a difficult election challenge is Sen. Pat Browne, the head of the powerful Senate Appropriations Committee. The Allentown-area lawmaker would not say whether he has made up his mind, or discuss alternatives to a window. "We're working through that," he said.

Many public officials believe that if the proposal for a two-year window gets a vote in the entire chamber, it would pass. That includes state Attorney General Josh Shapiro, whose office led the grand jury investigation.

In an interview Wednesday, Shapiro noted that the grand jurors who for two years heard evidence in the clergy abuse case specifically called for a two-year window among their policy recommendations. Other reforms included eliminating entirely the criminal statute of limitations for child sexual abuse and strengthening reporting laws.

"There are many senators about to ask Pennsylvanians for their vote in just a few weeks," Shapiro said. "And I think Pennsylvanians of all faiths have been shaken by this report and want to see their senators do something to hold people who abused children accountable, and be a check to the powerful institutions that enabled it."

Scarnati and his Republican backers are working behind the scenes to come up with an alternative, according to legislative and other officials familiar with the discussions. They are considering offering older victims a hybrid menu of options, including a victims compensation fund (which all of the state's eight Catholic bishops have endorsed) and a potential "civil registry" to publicly name child abusers, similar to a controversial one enacted in Ohio more than a decade ago.

Victims advocates have eschewed both. They say church officials have provided scant detail on how a victims compensation fund would be operated and financed, and note that it would only help victims abused by clergy.

As for a civil registry, they call it worthless, saying it allows institutions like the Catholic Church that enabled abusers to escape liability. In Ohio, the registry has been completely ineffective, according to lawyer and sex-abuse victims advocate Marci Hamilton.

"It's a joke," she said, "which is why it has not been replicated anywhere else."