By Kristina Peterson and Natalie Andrews 

WASHINGTON -- Lawmakers return to Washington on Monday to find a familiar contentious issue -- guns -- taking a priority over spending and immigration legislation that were expected to preoccupy their time for the next several weeks.

The Feb. 14 school shooting in Parkland, Fla., and President Donald Trump's subsequent calls on Congress to take action are expected to reboot an effort to tighten the national firearm-purchase background-check system. While no bills are assured of moving forward, even debating and voting on gun legislation will be politically fraught for many lawmakers of both parties just eight months before midterm elections.

Congress is most likely to consider a measure from Sens. John Cornyn (R., Texas) and Chris Murphy (D., Conn.) that would encourage states and federal agencies, including the military, to submit criminal-conviction records to the National Instant Criminal Background Check System, or NICS. Mr. Cornyn introduced the bill after the background-check system failed to prevent the gunman in a Texas shooting last November from purchasing weapons, despite his history of domestic abuse. Those records are required by law to be uploaded, but they can slip through the cracks.

The Cornyn bill passed the House in December, but there it was paired with legislation that would enable gun owners who legally carry concealed firearms in one state to carry them in the other 49 states -- a major expansion of gun rights. Critics of the concealed-carry reciprocity bill say it would trample on the prerogative of states to set their own standards for carrying guns in public.

The most immediate question is whether Senate Majority Leader Mitch McConnell (R., Ky.) will bring up the bill -- known as "Fix NICS" -- on its own, without the concealed weapons provision. On Monday, Florida's two senators, Republican Marco Rubio and Democrat Bill Nelson, plan to try to bypass Senate procedures and pass the bill with the unanimous consent of all 100 senators.

That route faces potential hurdles from at least two Republican senators, Mike Lee of Utah and Rand Paul of Kentucky, who have said they are concerned about how individuals flagged under the background check system would be able to appeal.

If the bill does pass the Senate, GOP leaders will have to decide whether they are willing to bring it up on its own in the House, without the concealed-carry reciprocity bill. That could face backlash from conservatives, aides said.

So far, House GOP leaders have shown little appetite to take up gun-control legislation. On Friday, House Majority Whip Steve Scalise (R., La.), who was seriously injured in a shooting last year, said on the Fox Business Network that the Florida shooting instead revealed shortcomings in law enforcement's handling of tips warning the gunman posed a threat.

Rep. Leonard Lance of New Jersey, who represents a swing suburban district, on Friday sent a letter signed by 18 other House Republicans urging House Speaker Paul Ryan (R., Wis.) to bring up the "Fix NICS" bill up for a stand-alone vote this week. Before the recess, Mr. Ryan told reporters that if the background-check bill were to pass the Senate, the two chambers would negotiate a compromise.

Most Democrats support the bill, though they have pressed for Congress to do more.

"Any step in the direction of preventing this kind of violence from happening, we're going to be there," said Rep. Tim Ryan (D., Ohio).

The activism from young students from Marjory Stoneman Douglas High School, the site of the shooting, has boosted Democrats' optimism. Since the shooting, the students have spoken out against lawmakers who have opposed gun-control legislation in the past and against those who accept money from the National Rifle Association.

"This feels so different and I'm so proud of those young people," Rep. Brenda Lawrence (D., Mich.) said. "Every time we bring up this discussion, we're squashed."

Many lawmakers and congressional aides remain skeptical that Congress would pass any changes to the nation's gun laws. Continued pressure from a Republican president, however, could persuade GOP lawmakers to take modest steps aimed at preventing more gun violence.

On Sunday, Sen. Pat Toomey (R., Pa.) touted a bill he crafted with Democratic West Virginia Sen. Joe Manchin in the wake of the 2012 Newtown, Conn., elementary school shooting. The bill would expand background checks to all online sales and sales at gun shows, with the goal of flagging people with criminal or mental-health histories that disqualify them from gun ownership. Currently, the checks are needed only for sales by federally licensed dealers. In 2013 the bill failed to win 60 votes needed to pass the Senate.

"I do think there are some members who were not supportive in the past who are reconsidering," Mr. Toomey said on NBC's "Meet the Press." "The president's expression of support for strengthening our background check system is very constructive... So I intend to give this another shot."

Among the possible hurdles to any gun bill getting 60 votes in the Senate is the fact that many Democrats from conservative-leaning states are up for re-election this year.

Since the Florida shooting, Mr. Trump has made multiple posts on Twitter on the matter, held meetings with victims, state and local officials at the White House and discussed his proposals at length on Friday before a crowd of conservative activists.

"We will do something. We will act," Mr. Trump said at the Conservative Political Action Conference. "I really believe that Congress is going to get it through this time," he added.

He is expected to host a bipartisan group of lawmakers to discuss gun violence on Wednesday, according to a White House official.

Mr. Trump has suggested Congress could tighten the background-check system and raise the minimum age for some gun purchases to 21. On Tuesday, he directed Attorney General Jeff Sessions to draft regulations that would ban "bump stocks," devices that increase the shooting efficiency of semiautomatic weapons. The president also has called repeatedly for select, trained educators to carry weapons on school grounds.

Amid the revived gun debate, lawmakers have until March 23 to draft spending legislation that will fund the government through the rest of the fiscal year, which runs through September. Earlier this month, congressional leaders struck a two-year budget deal that would raise federal spending by almost $300 billion above limits imposed by a 2011 budget law. Lawmakers are now writing detailed spending legislation under the deal's parameters.

The spending bill, which must be passed before the government's current funding expires at 12:01 a.m. on March 24, could also be a place where lawmakers tuck in any extension of an Obama-era program that has prevented the deportation of the so-called Dreamers, young undocumented immigrants brought to the country by their parents. Mr. Trump ended the program in September, but gave Congress until March 5 to pass a replacement. Meanwhile, two federal judges have halted the Trump administration's move to end the program; the Justice Department appealed.

In addition, Mr. Trump has asked for billions in funding for a wall along the Mexican border, as well as limits to family-based immigration and an end to the diversity lottery visa program which admits immigrants from underrepresented countries. After a week of debate earlier this month on a variety of immigration bills, the Senate didn't pass any immigration legislation.

--Peter Nicholas contributed to this article.

Write to Kristina Peterson at kristina.peterson@wsj.com and Natalie Andrews at Natalie.Andrews@wsj.com

(END) Dow Jones Newswires

February 25, 2018 14:25 ET (19:25 GMT)

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