WASHINGTON — House Democrats, seeking to pressure the Senate Republican leadership to take up gun safety legislation, broke away from their August recess on Tuesday to appear in the Capitol with victims of gun violence, who pleaded with Congress to act swiftly to prevent further bloodshed.
Six top Democrats called on Senator Mitch McConnell, the Republican leader, to bring senators back to Washington to pass two House bills: one mandating background checks on all gun purchases, including at gun shows and on the internet, and another extending the time the F.B.I. has to complete background checks.
“The time is not simply for reflection,” said Representative Steny H. Hoyer of Maryland, the Democratic leader. “The time is not for a moment of silence. The time for the Senate is to act. The time is to listen to the American people.”
Returning to Washington from their districts, the lawmakers shared stories from their constituents demanding action. Representative Debbie Dingell of Michigan, whose husband, John, was on the board of the National Rifle Association before his death in February, described attending a festival in her hometown in the days after mass shootings in Ohio and Texas. She said an Arab-American child approached her and asked, “Why do people hate us? Are we safe?”
“I shouldn’t be answering questions of mothers of kindergartners or of children themselves about whether they are safe or hated,” Ms. Dingell said, her voice rising. “We can’t keep going to our corners and not figuring out what we are going to do.”
On the other side of the Capitol, Senator Chuck Schumer, the Democratic leader, has also been pressing Mr. McConnell to take up the House legislation and intends to formally request that the Trump administration cancel its request for $5 billion in border wall funding and reallocate the money for other uses, including initiatives to address gun violence and violent white supremacy, according to a senior aide to Mr. Schumer.
Gun safety has long been one of the most divisive issues in Washington, but this month’s massacres in El Paso and Dayton, Ohio, have thrust it onto the congressional agenda in a way not seen since 2012, after the massacre of 26 children and staff members at the Sandy Hook Elementary School in Newtown, Conn.
Congress failed to take action in the wake of that tragedy; a bipartisan background check bill fell in the Senate in 2013. The House, now under Democratic control, passed a background check bill earlier this year, along with a bill extending the time the F.B.I. has to conduct background checks to 10 business days from three. But Mr. McConnell had refused to take up the measures because President Trump threatened to veto them.
But while Mr. Trump has said repeatedly that Mr. McConnell favors expanding background checks, the leader has not committed to taking up the bill, and he has said he has no intention of bringing the Senate back early to consider it.
Mr. Trump on Sunday telephoned Senator Christopher S. Murphy, a Democrat who has been one of the leading voices in Congress for gun control, an indication that the president is interested in pursuing legislation. Earlier in the week, Mr. Murphy had contacted the White House to indicate that he was willing to work with Mr. Trump on the issue, which prompted the call.
The conversation was positive, with Mr. Trump indicating that he was serious about persuading Republicans to act, according to officials familiar with their discussion. And the two agreed to set up a staff-level dialogue this week between their offices and those of Senators Patrick J. Toomey, Republican of Pennsylvania, and Joe Manchin III, Democrat of West Virginia, who are working feverishly to revive the background check legislation they wrote after the Sandy Hook massacre.
The N.R.A., which opposes gun registration in any form, has for years fought against background check bills, arguing that they “don’t stop criminals from getting firearms” and that some proposals “would deprive individuals of due process of law.” If such a bill passed and was signed by Mr. Trump into law, it would be the first significant federal gun safety law in a quarter-century.
Tuesday’s news conference comes as Democrats, including those on the presidential campaign trail, are rushing to embrace gun safety legislation and make it a campaign issue. Gun safety was a major topic of conversation at the Iowa State Fair over the weekend, which turned into a kind of contest to determine which Democrats could advance the most aggressive gun control measures.
And while House Democratic leaders are pushing for the background check bill, many Democrats are seeking to revive the assault weapons ban, which expired in 2004 and had barred the purchase of military-style semiautomatic assault rifles and high-capacity magazines like the gunman used in Dayton.
Former Vice President Joseph R. Biden Jr. called for an assault weapons ban in an opinion piece in The New York Times on Monday. On Tuesday, his campaign sent an email to supporters asking them to sign a petition asking Congress to reinstate the ban and said it already had 18,000 signatures.
The ban, though, is a nonstarter in the Senate, and even its chief sponsor, Representative David Cicilline, Democrat of Rhode Island, said Monday in an interview that the better strategy was to pressure Mr. McConnell to take action on the bills the House had already passed.
“We passed two pieces of legislation that will make a real difference, that are overwhelmingly supported by the American people,” said Mr. Cicilline, who is also a member of Democratic leadership. “I think the sense is: Let’s push hard to get the Senate to come into session or at least act on the two bills that we’ve already sent them. And then we can take up other ideas.”
Polls show that roughly 90 percent of the public supports expanded background checks, but Democrats were for years skittish about pursuing gun safety legislation. With more and more mass shootings, that has begun to change.
“The biggest thing that has changed is a cultural shift with all of these shootings,” said Celinda Lake, a Democratic pollster. “When the mayor of Dayton said something like they were the 250th city to have a mass shooting this year, when you have all of the people that have been killed — and not just in mass shootings, every day on the streets — I think there is just a whole different momentum for doing something.”
The political landscape is changing as well. Last year, two Democrats — Representatives Jason Crow of Colorado and Lucy McBath of Georgia — flipped Republican seats in swing districts after campaigning on a promise to fight gun violence. Mr. Crow is a military veteran. Ms. McBath’s 17-year-old son, Jordan Davis, was shot and killed seven years ago at a Florida gas station by a white man who complained that Jordan and his friends were playing music too loudly in their car.
“It’s a false choice between the Second Amendment and responsible regulation and prevention,” Mr. Crow said in an interview. “I come at this from my frame as a lifetime hunter and a gun owner. It’s a false choice, it’s one that we now reject. We can respect the cultural heritage of responsible gun ownership in America but also save thousands of lives.”