Democrat Jason Crow greets canvassers as they head out to round up votes in Aurora, Colo., on Oct. 20. (David Zalubowski/AP)

Democratic congressional candidates in suburban swing seats are embracing restrictions on firearms as election-related spending from pro-gun groups, including the powerhouse National Rifle Association, has plummeted.

The willingness to campaign on gun-control policies, including universal background checks and restrictions on military-style weapons, runs counter to past elections, when candidates feared the topic could isolate moderate voters or prompt reprisal from the NRA, whose spending is down about 68 percent since the 2014 midterm elections. Groups calling for gun-control measures have injected nearly $12 million into campaigns, the most they have spent in an election cycle since at least 2010.

The candidates’ emboldened approach, combined with the changes in spending trends, reflects a shift in the politics of gun policy over the past two years. Polls show Americans are becoming more supportive of stricter firearm laws amid a spate of mass shootings.

“The convention in swing districts like this is, don’t take it on, not in a purple or light blue district. It’s a wedge issue,” said Jason Crow, a Democrat running against Rep. Mike Coffman (R) in Colorado’s 6th Congressional District in the Denver suburbs. “But I believe the danger is in not taking this on anymore.”

Crow, a U.S. Army Ranger veteran who served in Iraq and Afghanistan, often talks about hearing the news that a gunman with a military-style rifle killed 12 people at a movie theater in Aurora, which is in the district.

“I’d used military-style assault weapons at work,” he said in an interview. “And had them used against me.”

Crow has called for a ban on the weapons. Coffman’s campaign brushed off Crow’s stance as a fundraising strategy. Coffman, who was a co-sponsor on a bill on school safety and has pushed for guns to be taken from people who are determined to be potential threats, has an “A” rating and donations from the NRA.

“I certainly support the Second Amendment; however, I believe in responsible gun ownership,” Coffman said in an interview with Denver Westword.

On Thursday, days after 11 people were killed in a shooting at a Pittsburgh synagogue, Everytown for Gun Safety launched a $700,000 ad buy against Coffman.

Support for stricter firearm laws has grown. According to an October Gallup poll, 61 percent of Americans said firearm laws should be more strict — a dip from 67 percent in March but still at a high point dating back to 2004.

For the past few years, Everytown had focused on changing laws in states where it saw a chance to make inroads, including Nevada and Washington. It is now trying to replicate that with congressional and statewide races.

“The momentum is with us, the NRA is on its heels, and we think that it’s an opportunity to keep redrawing the map,” said John Feinblatt, president of Everytown.

While most of the beneficiaries of Everytown’s money and endorsements are Democrats, the group — backed by billionaire and former New York mayor Michael Bloomberg, a potential 2020 presidential candidate — has also endorsed Republicans in tight races, including Rep. Carlos Curbelo (R-Fla.).

Many candidates are also taking a more nuanced approach to gun control than politicians have in the past. Democrats and Republicans are using the term “gun safety” rather than “gun control” as a way to convey that they want to enact policies such as requiring universal background checks or safe storage of guns, not banning certain classes of weapons

While gun policy is not the top issue for most congressional battleground races, a recent Washington Post-Schar School poll found 41 percent of people in battleground districts said gun violence was an “extremely” important issue in their vote for Congress this year. Gun control also resonates with younger Americans. A poll conducted in October by the Harvard Kennedy School’s Institute of Politics showed school shootings were the top concern among Americans from the ages of 14 to 29.

Public outcry after the February school shooting in Parkland, Fla., which left 17 dead, further shifted the political landscape going into midterm season. In its wake, 19 states passed some form of gun legislation. They include Florida, where Gov. Rick Scott, a Republican who is now in a tight race for Senate, signed a suite of gun-control bills into law.

The shift is happening in congressional and local races. Democratic gubernatorial candidates in states including Florida, Georgia, New Hampshire and Connecticut have all made gun control a major issue in their campaigns.

Some congressional candidates are using their personal experience with gun violence in their campaigns. In Georgia’s 6th Congressional District, Democrat Lucy McBath speaks about how her son, Jordan Davis, a black teenager, was killed by a white man over a dispute about loud music in Florida.

In California’s 48th District, Democratic candidate Harley Rouda is using gun control as a pivotal issue in his deadlocked race against Rep. Dana Rohrabacher (R). The state’s 25th Congressional District race, between Rep. Steve Knight (R) and challenger Katie Hill (D), has also featured gun-control messaging.

Hill emphasizes she is a gun owner who comes from a family of law enforcement officers and veterans. She is calling for universal background checks and raising the age to purchase firearms to 21.

“I believe that respecting the Second Amendment and advocating for gun safety measures are not mutually exclusive,” Hill said in a statement.

The NRA and other groups supporting gun rights have been far less active this election after ramping up their spending on advertising in every other cycle since 2010, according to an analysis by the nonpartisan Center for Responsive Politics.

In 2016, the NRA and other gun rights groups shelled out nearly $55 million on media and advertisements, CRP data shows. This election, their spending has plummeted to roughly $9 million, the majority of which has come from the NRA.

The NRA has spent 2018 fighting a torrent of criticism, facing direct challenges by students, activists, corporate America and politicians. Perhaps in a reflection of the criticism, some Republican candidates running in tough congressional districts this year returned or did not deposit donations from the group, Mother Jones found.

States are also probing the NRA’s insurance products; the group is embroiled in a lawsuit with New York over its Carry Guard insurance policy.

But it remains a powerful political force. It is active in lobbying and has a national grass-roots operation that mobilizes voters.

The NRA did not return requests for comment.

The organization is boosting GOP Senate candidates in Missouri, Tennessee, Arizona, Indiana and Montana. Last week, the NRA’s political action committee spent nearly $900,000 over two days supporting Republicans in key Senate races, Federal Election Commission records show.

In comparison, gun-control groups have spent nearly $12 million this election, according to an analysis of federal spending records by the CRP. While their spending still pales in comparison to the massive amounts gun rights groups injected in previous election cycles, it is the most gun-control groups have spent in one election cycle going back to 2010, CRP records show.

Giffords PAC, a gun-control super PAC founded by former congresswoman Gabrielle Giffords, who was shot at a campaign event in 2011, and her husband, Mark Kelly, has injected nearly $6 million into races around the country, including in Texas, Virginia and Minnesota. The group says far more political ads on gun control are running this year than in previous cycles.

“The change is pretty profound, and it’s been lightning quick,” said Peter Ambler, Giffords’s executive director.

Emily Guskin contributed to this report.