WASHINGTON — The push for Congress to enact new federal gun restrictions following the shooting deaths of 17 students and faculty inside a Florida high school this month faces formidable obstacles in Congress, where key Republicans have met calls for action with skepticism – or, more often, silence.

Pressed by survivors of the Feb. 14 massacre, President Trump has said he is willing to consider new laws improving federal background checks, raising the minimum firearm purchase age and banning certain gun accessories. But neither House Speaker Paul Ryan, R-Wisconsin, nor Senate Majority Leader Mitch McConnell, R-Kentucky, has publicly acknowledged the possibility of new legislation.

The hands-off approach from the top leaders reflects divisions within the Republican Party between lawmakers representing politically moderate, often suburban areas where there is wide support for new gun laws and those representing more rural, solidly Republican states and districts where any attempt to restrict firearms could be seen as a creeping attack on the rights of law-abiding gun owners.

While the former group has been increasingly vocal over the past week, it is the latter who constitute the bulk of the Republican majorities in the House and Senate – and are likely to dictate what legislation, if any, is considered in response.

What remains to be seen is whether the growing drumbeat for revisions – from Republican moderates, from major corporations, from Trump and from the country overall – will change this long-standing dynamic.

“I haven’t heard a strong, loud outcry for gun control,” said House Majority Whip Steve Scalise, R-La., who in an interview Friday called for rigorous congressional oversight of the multiple institutional failures that preceded suspected gunman Nikolas Cruz’s rampage inside Marjory Stoneman Douglas High School in Parkland, Florida.

Shot himself last year by a gunman who targeted Republican lawmakers at a congressional baseball practice, Scalise has remained an outspoken opponent of new gun laws – and an embodiment of the political center of gravity within his party.

“All of these failures of government to properly deal with mentally ill people make people strengthen their resolve on why they need a gun for their own protection,” he said. “It concerns people when more threats come to the gun rights of law-abiding citizens when government failed at every level when they should have stopped this kid.”

BIPARTISAN EFFORTS UNDERWAY

Yet the Florida shooting has created fresh uncertainty about the chances for new gun restrictions. The list of major corporations that have cut ties with the National Rifle Association keeps expanding. And multiple Republican lawmakers have come forward in recent days to challenge their party’s Second Amendment orthodoxy.

Rep. Carlos Curbelo, R-Florida, who represents a Miami-area district, wants the minimum age for any firearm purchase to rise from 18 to 21, among other changes. Rep. Brian Mast, R-Florida, a disabled veteran who represents a closely divided district just north of Parkland, has called for a new ban on military-style semi-automatic rifles, such as the AR-15 police say was wielded by Cruz. And 19 House Republicans, led by Rep. Leonard Lance, R-New Jersey, have called on Ryan to hold a vote this week on a bipartisan bill intended to close gaps in the federal background check system.

Members of a bipartisan group that includes numerous moderate Republicans, the Problem Solvers Caucus, have already begun informal talks about assembling a package of legislation to meet the calls for action, said Rep. Tom Reed, R-New York, the group’s co-chairman.

“We’re in a leadership position in both the House and the Senate, and in the White House,” Reed said of his party, “and so with leadership comes responsibility to address these problems as they arise.”

Among the ideas the group’s members have floated, he said, involve expansions of background checks, changing mental-health laws to allow more aggressive interventions for those with mental illnesses and a ban on accessories that allow semi-automatic rifles to be fired at the pace of a fully automatic weapon. One such device, known as a “bump stock,” was used by the shooter in the Las Vegas massacre in October.

LEADERS OUT OF THE PUBLIC EYE

Top Republican congressional leaders have not endorsed those proposals, or any others. They have navigated the treacherous politics that follow each gun rampage by lamenting the lives lost, praising the first responders and calling for facts to be gathered before taking action. The pattern has repeated itself regularly over the past three years, after bloodshed in San Bernardino, California; Orlando, Florida; Sutherland Springs, Texas; and Las Vegas.

Both Ryan and McConnell have been quiet since the immediate aftermath of the Parkland massacre, a strategy that has been aided by a weeklong congressional recess that kept both men out of the public eye.

The day after the shooting, Ryan said Americans “just need to step back and count our blessings” and “think less about taking sides and fighting each other politically.” The same day, McConnell delivered brief remarks on the Senate floor. To say “such brutal, pointless violence is unconscionable is an understatement,” he said. Neither has expanded since on their comments.

Both men come from states with strong traditions of owning firearms, and both hold top ratings from the National Rifle Association. Ryan is an avid hunter who prefers stalking deer with a bow but has also described saving up as a teenager to buy a 20-gauge shotgun for pheasant shoots.

Those familiar with McConnell’s thinking on guns over the years say he approaches it not strictly from an ideological perspective.

“I would consider Kentucky to be a pro-gun state,” said Scott Jennings, a former McConnell strategist. “But I think he’s someone who has always been willing to be pragmatic when solutions present themselves that can garner” the necessary 60 votes to advance legislation in the Senate.

THE FIX NICS ACT

It is not entirely clear what gun-related measures could clear that threshold. One measure that could attract broad support is a bill aimed at beefing up the National Instant Background Check System, or NICS, by ensuring agencies and jurisdictions submit data that could be used to disqualify questionable gun buyers. The Fix NICS Act is co-sponsored by Sens. John Cornyn, R-Texas, and Chris Murphy, D-Connecticut, and has the backing of the NRA.

More aggressive measures are in the works, including a measure from Sens. Jeff Flake, R-Arizona, and Dianne Feinstein, D-California, that would raise the minimum purchase age for nonmilitary buyers of rifles from 18 to 21. Sen. Patrick Toomey, R-Pennsylvania, has said he is willing to revisit a measure he co-sponsored with West Virginia Democratic Sen. Joe Manchin III that could mandate more expansive background checks; a previous attempt to pass it in 2013 after the Sandy Hook Elementary School killings narrowly failed.

And then there’s Sen. Marco Rubio, R-Florida, who could emerge as a more prominent player in the Senate gun talks. Rubio recently came out in favor of raising the minimum age on rifle purchases and said he is open to limits on high-capacity ammunition magazines.

Despite such efforts, there is a keen sense among members of both parties that lower-profile Republicans are not as warm to these ideas – even amid a growing sense in some Republican circles that doing nothing on guns following shooting after shooting is untenable.

Murphy, a vocal gun-control advocate who plans to meet with White House officials in the coming days, said the current landscape is “different” but that he doesn’t yet see it as “a tipping point.”

The conversation is especially fraught in this pivotal election year, in which Republicans are nervously defending control of the House and Senate. Both Ryan and McConnell are mindful that gun legislation could prompt conservative primary challenges for their members, which in some districts and states could imperil seats in the general election.

PRESSURE FROM ALL SIDES

The politics are also treacherous for Democrats, whose leaders are squarely behind new gun-control legislation but whose rank-and-file varies greatly on how far that push should go.

Rep. Ted Deutch, D-Florida, who represents the district that includes Stoneman Douglas, floated a complete ban on semi-automatic rifles during a CNN town hall this week. But more moderate Democrats are not willing to go anywhere near that level of restriction.

The gun debate will pose a particular political challenge to Senate Minority Leader Charles Schumer, D-New York, who will have to decide how hard he wants to push new gun restrictions as he also struggles to protect incumbents up for re-election in conservative states where support for gun rights is widespread.

In other words, the pressure is coming from all sides.

Al Hoffman Jr., an influential Republican donor based in Florida, is trying to pressure lawmakers to support an assault weapons ban. Mast, who on Friday came out in support of a ban, is among the members Hoffman said he has contacted.

“I’m going to make sure that we’re going to contact every Republican we can,” Hoffman said in an interview, identifying McConnell and South Carolina Republican Sen. Lindsey Graham as targets.

But he is unlikely to get much of a hearing among Republican lawmakers representing rural states where gun rights are sacrosanct.

“I am unconvinced that particular shooter would not have committed a crime if he had a different kind of rifle or a pistol in his hand,” said Sen. James Lankford, R-Oklahoma, who does not favor a ban on assault weapons or high-capacity magazines.

HARD RIGHT STILL FEELS SECURE

For Ryan, even if he were to set aside his personal views on gun rights, any move toward action on gun control would be complicated by the intricate politics of the House Republican Conference, whose right flank is vigilant over potential betrayals of conservative priorities.

The Fix NICS Act, for instance, passed the House in December, but only after it was attached to a controversial NRA-backed bill mandating states recognize concealed-carry permits issued by other states. Conservatives are warning against decoupling the measures despite the NICS bill’s broad bipartisan support.

House Republican aides not authorized to comment publicly on the gun debate said that, much as with the immigration issue, the only way Ryan and other Republican leaders would be compelled to act on guns would be with Trump’s full-throated support, giving cover to conservative lawmakers who might otherwise be vulnerable to Republican primary challengers.

Trump so far has been all over the map in floating responses to the Parkland tragedy, from a vague call for “comprehensive background checks” to a proposal that would encourage some teachers to carry weapons in the classroom.

Rep. Mark Meadows, R-North Carolina and chairman of the hard-right House Freedom Caucus, said most his party’s lawmakers are feeling perfectly secure in their gun views.

“I think there’s a whole lot of people who want to protect their Second Amendment rights and don’t want a slippery slope to infringe on that,” he said.