Nearly two weeks after back-to-back mass shootings killed at least 31 people and injured dozens more in El Paso and Dayton, Ohio, gun-control groups are pushing lawmakers to act on long-dormant gun policy measures.

And this time, activists say, momentum is on their side.

That’s thanks in large part to a burst of grass-roots organizing around the country. About 20,000 members of the Brady Campaign have called, emailed or collected signatures over the last two weeks asking Senate Majority Leader Mitch McConnell (R-Ky.) to call the Senate back from recess to take emergency action on gun legislation.

This weekend, thousands of volunteers with Moms Demand Action, the grass-roots arm of Everytown for Gun Safety, will hold rallies in all 50 states to urge senators to expand background-check laws and “red flag laws,” which would allow law enforcement or others to take a person’s firearms away if they are deemed a danger.

Public support for gun control has grown over the past decade, making the movement more palatable, activists say. But anger in the wake of the latest string of high-profile mass shootings has also tipped the scales.

“People are fed up. This keeps on happening,” Christian Heyne, vice president of policy for the Brady Campaign to Prevent Gun Violence. “The response to this from a small few people in one body of our federal government of Congress is the same. That’s unbelievably frustrating.”

Simultaneously, the groups are emboldened by what they see as a vacuum created by turmoil within the National Rifle Association. (The NRA denies its influence is slipping and has been talking directly to the president and others in the White House.) Gun-control activists are also aware of — if not completely reassured by — President Trump’s comments that he would support expanded background checks.

“The fact that Donald Trump and Mitch McConnell are openly discussing universal background checks and other gun-safety measures that we support is a powerful signal about the pressure” they feel from gun-safety groups, said Peter Ambler, executive director of the advocacy group Giffords.

Shannon Watts, founder of Moms Demand Action, said she was encouraged after seeing “hearts and minds change” since the latest mass shootings, including among prominent Republicans. Two days after a mass shooting in Dayton, Ohio, left nine people dead, the state’s Republican governor, Mike DeWine, called for expanded background checks and other gun-control measures. Rep. Michael R. Turner (R-Ohio) also announced his support for other gun-control measures.

“After the two shooting tragedies in a row . . . it was very obvious that lawmakers were open — including some lawmakers who had never been open before to acting on this issue,” Watts said. “We are definitely going to keep the momentum going for the next three weeks until the Senate comes back.”

Moms Demand Action is scheduling meetings with every district office in states it views as NRA strongholds, including Texas and Florida. It is also running television ads in Kentucky to press McConnell to convene the Senate in an emergency session.

But persuading the White House and the Republican-controlled Senate to act will be an uphill battle.

A McConnell adviser said the Senate majority leader does not fully support expanded background checks — Trump had suggested McConnell was “totally on board” — but that he is inclined to have a debate. McConnell has polled Republican senators on the issue, this adviser said.

Interviews with Trump administration officials reveal a back-and-forth unfolding in the White House, as lawmakers and the NRA attempt to lobby the president after he said last week he would be open to strengthening background checks.

White House officials met with staffers from the office of Sen. Joe Manchin III (D-W.Va.) Tuesday but made no commitment to support the bipartisan bill expanding background checks that Manchin drafted with Sen. Patrick J. Toomey (R-Pa.) after the Newtown shooting in 2012, people familiar with the meeting said.

Administration officials said they are assembling a less aggressive package on background checks than the Toomey-Manchin legislation, and are planning a trip to Bedminster, N.J., to present their alternative to the president while he is on vacation.

Families who lost their first-graders in the Sandy Hook massacre met the president during a “listening session” last year and have since used that connection to engage White House staff on gun issues, Nicole Hockley, the co-founder of Sandy Hook Promise said. The president, she said, appears to be listening.

“It’s not a matter of if, it’s a matter of when,” said Hockley, who has focused her pressure campaign on pushing universal background checks and an incentive for states to pass red flag laws. “We believe that the country has an appetite for those laws and that it would be a very smart play for the White House, but it would also really help save a lot of lives.”

Sen. Richard Blumenthal (D-Conn.), who is working with Sen. Lindsey O. Graham (R-S.C.) on a bipartisan bill on red flag laws, said he would believe Trump’s support of gun-control measures “when I see it.”

“My general feeling is one of hope, but we’ve been down this road on other proposals, you know,” he said. “[It] could well be a turning point, if the White House is serious this time.”

There is skepticism inside Chief of Staff Mick Mulvaney’s orbit about any sort of major gun control deal, and Mulvaney has kept in touch with opponents of new legislation, including NRA officials.

And key Republican legislators, including Rep. Jim Jordan (R-Ohio) and Sen. David Perdue (R-Ga.), have discouraged action on gun control, White House officials said.

“We are hearing concerns from some of our Republican colleagues at the state level and federal level on proposals,” Jordan said. “Lots of my colleagues have the same concerns that I do on the background check legislation and with the red flag legislation.”

Trump has mused to aides that the NRA is a weakened political body that he can take on, but remains concerned his supporters would not prefer such legislation, advisers said.

“He is testing the waters,” said a senior White House official, “but he’s a lot more determined to do something than others in the building are.”

A number of Fox News hosts have also argued against gun control measures, which could be influential with the president, two senior White House officials said.

Watts, for one, is not holding her breath waiting for Trump to steer the conversation on background checks.

“I think the president is a wild card at these moments. It’s really in the hands of the Senate,” Watts said. “If the president believes this is important, he will demand Mitch McConnell act and he will put this legislation in front of senators to vote on. That seems possible.”

Their movement has been buoyed by shifting public opinion in favor of stricter gun laws. Gallup polling finds support for stricter laws is down slightly this year, to 61 percent, but significantly higher than before 2012. Other polls find about 9 in 10 Americans support requiring background checks for all gun purchases, including more than 8 in 10 Republicans, Democrats and independents.

David Chipman, a senior policy analyst for Giffords, says the NRA’s difficulties have also created room for “responsible” gun owners to make progress on gun safety issues. The organization has organized gun owners in states known as NRA strongholds to advocate for new restrictions.

In recent months, Giffords has founded new gun owner coalitions in Colorado and Minnesota, and it has been active lobbying at the state level lobbying — and says it is seeing results. In Colorado earlier this year, the state legislature approved “red flag” legislation that establishes a process for removing firearms from people deemed to be in an emotional crisis. Members of the new gun owners coalition established by Giffords testified at the state House before the vote approving the legislation.

On Aug. 20, the group plans to launch a coalition for Texas gun owners.

“The NRA isn’t really representing the values of gun owners and has opened up a space” for concerned gun owners to express themselves on common-sense solutions to limit violence, Chipman said.

NRA members reject the notion that they’re losing organizational steam. Members tout the continued grass-roots power of their organization, citing their own state victories.

“The power of the NRA resides in its grass-roots advocacy. The NRA has notched together a string of recent victories,” NRA spokesman Andrew Arulanandam said, noting the group had marshaled opposition to gun-control measures during this summer’s special legislative session in Virginia.

“With many in the anti-gun community writing the obituary of the NRA, we are scoring big wins in the legislative, legal and public policy arenas,” he said.

Some gun-control organizations are skipping politicians altogether.

Guns Down America, which was formed after the Pulse nightclub massacre in 2016, has focused the bulk of its recent efforts on petitioning Walmart to stop selling guns and to stop supporting NRA-backed politicians, and to devote its lobbying heft to advocating for stricter gun laws.

“Mitch McConnell has built his entire political career by carrying water for the NRA . . . so it’s difficult to imagine, absent some kind of real wave of pressure, that he will all of a sudden find Jesus on this point and actually represent what his constituents want,” executive director Igor Volsky said. “Federal legislation takes a long time, but people are dying today from guns. So you have to start thinking about what other actors you can pull into this effort.”

The group held a rally Saturday at a Walmart in Florida where students at Marjory Stoneman Douglas High School ran for cover when their campus was attacked by a former student last year. The protest marked one week since 22 people were killed at a Walmart in El Paso.

Walmart has said it would remove from its stores displays of violent video games — but not guns.

Guns Down America has asked its members around the country to hold similar rallies at their local Walmart.

“Walmart has shown that they take the safety of their customers and employees seriously. Walmart is also the largest gun seller in America,” Volsky said. “That means if it were to, say, stop gun sales and no longer give money to politicians who get money from the NRA, that’s really going to create some shock waves in the gun industry — and also the halls of Congress. It could actually shake up the political conversation.”

Scott Clement and Seung Min Kim contributed to this report.

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