There is also a certain political expediency: Many of the Democrats airing misgivings about the N.R.A. and its views are now competing in primaries where they are playing to an audience of fellow Democrats and not yet the entire electorate. Their hostility to the N.R.A. in the spring could certainly fade by the fall, but in past election cycles, many candidates would have regarded openly crossing the N.R.A. as too risky even in primary races.
“I don’t know that voters would have been more receptive; I think that candidates would have been more timid,” Stacey Abrams, a Democrat running for governor of Georgia, said last month before she addressed a March for Our Lives rally near the southern tip of the Appalachian Trail and promoted her history of poor ratings from the N.R.A.
To be sure, some Democrats in conservative-leaning states, like Ms. Abrams, have long been willing to challenge the group, especially in urban areas — but there were rarely very many of them. Meanwhile, rural Democrats often did the opposite, and actively courted the N.R.A., whose seal of approval and potent ability to mobilize its members could lift a candidate of either party to victory.
That era is not completely over. But many Democrats have grown wary of an organization that they believe has effectively evolved into an extension of the Republican Party, and they have begun to wonder whether they would be better off putting some distance between themselves and the N.R.A. The most fervent supporters of gun rights, some Democrats reason, are unlikely to support their campaigns no matter what they do.
“I think those that are hypersensitive to this issue are likely not going to be voting for us anyway, and I understand that, because there are voters who believe that any discussion of the Second Amendment is the compromising of the Second Amendment,” said Walt Maddox, a Democratic candidate for governor of Alabama. “But I believe the vast majority of Democrats, independents and Republicans are not fearful of a discussion on this matter, especially if it’s reasonable, measured and common sense-oriented.”
For his own part, Mr. Maddox declares allegiance to the Second Amendment, but he declined to fill out the questionnaire that the N.R.A. sends to candidates. In the N.R.A.’s view, refusing to complete the questionnaire is “often an indication of indifference, if not outright hostility, to gun owners’ and sportsmen’s rights.”
Other Democrats have mounted far more pointed critiques of the group. The Democratic Party in Virginia, a state that retains a conservative streak despite recent Democratic successes, recently issued a statement referring to N.R.A. “blood money” and declaring that Virginians were excited about “kicking out politicians who value National Rifle Association money over the safety of their sons and daughters, mothers and fathers.”
And in Kentucky, a Democratic state representative from an overwhelmingly conservative district stood on the House floor in February to call for new gun control measures, and said he was surrendering his A rating from the N.R.A.
Some Republicans have also calculated that they can now afford to cross the group to some extent. Gov. Rick Scott of Florida, who is running for the Senate this year, recently signed a Republican-backed gun-control package that was almost immediately challenged in a lawsuit by the N.R.A.
The mass shooting in Parkland, which helped prompt the legislation Mr. Scott signed, appears to have been a political turning point even in places like Montana, which has one of the nation’s highest rates of gun ownership and where candidates often talk about their hunting credentials.
At a candidates’ forum less than a week before the Parkland shooting, the Democrats vying for the party’s House nomination — there were then five — were asked whether they supported expanded background checks for gun purchasers. None said yes. Then came the rampage in Florida.
In short order, the race was infused with fresh calls to ban bump stocks, outlaw military-style weapons like the AR-15 and eliminate loopholes for sales at gun shows.
Mr. Heenan, one of the candidates in the race, soon released an essay apologizing for not giving “a more straightforward answer” to a grandmother who had asked him how he would help prevent gun violence.
Another candidate, Kathleen Williams, made prevention of gun massacres central to her platform, and later said, “If the N.R.A. wants to give me an F for that, then I will proudly stand with all of you and say that F means ‘fearless.’ ”
Lynda Moss, who is also running for the seat, spoke this week about a column she wrote years ago, when she described “how Montana’s gun policies became a facade of the N.R.A. — a false front used to broadcast fear and misinformation perpetuating the myth of the Wild West.”
Some supporters of gun rights said they were skeptical that attacking the N.R.A. would do any of the candidates much good in a state like Montana, where gun ownership is deeply entwined with the state’s history and culture.
“In Montana, every candidate is going to say, ‘I’m going to support the Second Amendment’ — and then some will add, ‘but,’ ” said Gary Marbut, the president of the Montana Shooting Sports Association, who has helped push nearly 70 gun rights bills into state law since the 1980s. The suddenly vocal critics of the N.R.A., he said, were “clearly political opportunists.”
The group backed the Republican incumbent in the House race, Greg Gianforte, in a special election in 2017 and is expected to do so again this year, when he is favored to win re-election. Neither the N.R.A. nor Mr. Gianforte’s campaign responded to requests for comment for this article.
Some Democrats in the state are confident that their party can succeed with a candidate who pushes away from the N.R.A. but finds a way to appeal to individual gun owners.
“We’ve hit a moment in time where the N.R.A. is denigrating a whole lot of responsible gun owners, so it’s not that surprising that folks finally say, ‘Enough’s enough — they don’t represent me, and they don’t represent either the mainstream of America or the mainstream of firearm owners,’ ” Gov. Steve Bullock, a Democrat, said in an interview in his office at the State Capitol.
Still, some Democrats in the race have remained cautious. Grant Kier, who is seen as one of the front-runners in the primary along with Mr. Heenan, recently called Mr. Marbut of the sport-shooting group to discuss gun rights.
“I think somebody who doesn’t respect people’s gun rights is not going to do well in Montana, period, regardless of the N.R.A.’s involvement,” Mr. Kier said. “I don’t see myself as running against the N.R.A.; I see myself as running against Greg Gianforte.”
He said he sees health care, not gun safety, as the dominant issue in the campaign. “I think that being sensitive to people’s desires to find sensible gun laws in our state and country is important, but I think there are far more issues on people’s minds that we need to be working on, too, and I think that’s how we win this election,” he said.
As the June 5 primary approaches in Montana, where the State Constitution decrees that the right to bear arms “shall not be called in question,” even those Democrats who have expressed deep misgivings about the N.R.A. appeared eager to show that they are not anti-gun.
“We love our wildlife, and we love a good elk burger,” Ms. Williams said. “That’s different than things that threaten our kids at school.”