The next contender in the fight to knock the most feared lobbying association in the United States off its powerful perch is a 43-year-old former stay-at-home mother from suburban Indianapolis named Shannon Watts.

With access to Michael Bloomberg's deep pockets and the force of more than 2 million dedicated supporters, Watts in recent months convinced the CEOs of several major U.S. companies to take a stand against guns in their stores and restaurants. Her group helped get laws passed in a few states that make it harder for perpetrators of domestic violence to get firearms.

And on Tuesday, Watts' organization, Moms Demand Action for Gun Sense in America, kicks off a new campaign meant to more directly challenge the mighty National Rifle Association on the gun group's home turf: Statehouses and Congress. The group will announce its endorsements for about 110 federal and state candidates for public office, and will roll out two television ads meant to persuade voters to embrace "common sense" gun restrictions, such as expanded background checks.

"It makes our moms feel like badasses to take on the most powerful lobbying organization in the country," Watts told The Huffington Post last week.

The new push comes after the group lost some big fights to the NRA in confrontations that underscore the limits of the moms' brand of volunteer-led grassroots activism -- especially at the state level, where entrenched gun lobbyists have an outsized voice.

This month, for example, Missouri's legislature gave final approval to a law that allows school districts to arm teachers without notifying parents. It also lowers the concealed carry age to 19 and nullifies local restrictions against carrying firearms in public. The vote came after the moms bombarded legislators with Facebook messages, tweets and letters.

Lobbying disclosure records reveal that at the same time, the NRA was buying leading Missouri lawmakers lunch: $1,700 worth of food and beverages in the first half of 2014.

Watts acknowledged that the NRA has a big head start, but insisted her group has made huge strides, fueled by the enthusiasm of moms who relish the challenge of taking on the mighty NRA.

"We're tired of a vocal minority of gun extremists making all the laws," Watts said.

Before she was a thorn in the side of the NRA, Watts was a part-time public relations consultant, raising her five children in an upscale neighborhood in suburban Indianapolis.

In July 2012, her then 12-year-old son watched a newscast about the mass shooting at a theater in Aurora, Colorado. He had plans to see the movie the next day. During the show, he had a panic attack and had to leave the theater.

"The barrier of innocence was broken," Watts said. When 20 elementary school children were massacred later that year in Newtown, Connecticut, Watts said her son's reaction was even more frightening. "He didn't have a reaction at all. He realizes that this is what happens in America, that no one is safe from gun violence."

Watts did what many people do when they feel outraged: She took to Facebook, announcing her intention to launch a new group to confront the scourge of gun violence in the U.S. to a grand total of about 75 friends. "Its not like I was a social media phenom," she said. "I was just so angry and outraged that I felt that next time I'd be culpable if I did nothing."

An acquaintance who saw her post connected Watts with a woman in Brooklyn who had written something similar on her page, and Moms Demand Action was born. Watts, who had held high-profile positions at the agribusiness giant Monsanto and elsewhere, has proved a natural at serving both as a spokeswoman for the gun control movement, and its effective CEO.

Moms Demand Action now has chapters in all 50 states. Over the past 13 months, the group pushed Starbucks, Sonic, Chili's, Chipotle, Target, Jack in the Box and Panera Bread to announce they no longer welcome armed customers.

In December of last year, Watts said she was approached with an offer too good to refuse: a merger with Michael Bloomberg's Mayors Against Illegal Guns that would allow her group access to the philanthropist and former mayor's wealth. The two organizations now operate under the umbrella Everytown for Gun Safety. Bloomberg later pledged $50 million a year to take on the NRA, and candidates that support its agenda.

The merger has proved transformative, allowing Moms Demand Action to hire staff and launch expensive ad campaigns, such as a current six-figure push to convince the grocery chain Kroger to say no to guns.

It has also paid dividends for Bloomberg's mayors group, which had the support of elected officials, but not much neighborhood-level buzz. As spokespersons for the cause, moms represent a significant upgrade from the prickly Big Gulp-banning ex-mayor.

Yet there is a risk the association with Bloomberg may tarnish the moms' grassroots brand. Watts spends one day a week in New York, in a high-floor office decorated with expensive aquariums and staffed with Bloomberg confidants. Though she insisted Moms Demand Action operates independently, gun groups have played up the link to argue that the moms are nothing but a front for Bloomberg and his billions.

Watts said the moms were energized about the merger, which gives them resources to directly challenge the NRA and the lobby's long influence over the political process.

The NRA is taking Watts' rise seriously. In September, the organization's in-house magazine published a story that asserts that she is a fraud, because she did sideline PR work while describing herself as a stay-at-home mom.

The artwork that accompanied the piece depicts Watts in a 1950s housedress, surrounded by an iron, a skillet (oddly, filled with french fries) and other totems that suggest authentic moms concern themselves with cooking and cleaning, not consulting. The piece was roundly criticized as offensive and out-of-touch.

"I mean, seriously, are there no women who work at the NRA?" Watts said. "These sexist lines of attack benefit us."

Watts said she routinely receives threatening phone calls and letters. Not long ago, someone posted a doctored photo on Facebook showing her with a knife in her head and blood running down her face. (Mother Jones has extensively chronicled the threats and sexist remarks.)

"I've learned about an underbelly of America I didn't know exists," Watts said.

On Tuesday, Watts will appear in Portland, Oregon, to premier the group's ad for Oregon Gov. John Kitzhaber, a Democrat who has supported gun control legislation, and is seeking re-election. In the clip, Paul Kemp holds a photo of his brother-in-law Steve Forsyth, who was killed by a gunman at a Portland mall in 2012.

"It was the worst day of my life," Kemp says. "I'm a gun owner," he continues. "The majority of gun owners want background checks in place." The ad concludes with an endorsement of Kitzhaber by Moms Demand Action.

For Watts, political endorsements mark a significant departure from a low-budget strategy that has thus far relied largely on local volunteers deploying social media activism. When taking on Target, for example, the moms circulated photos that so-called open carry activists took of themselves inside the stores, toting rifles and other long guns. The jarring images (see below) went viral, along with the hashtag #OffTarget.

Politicians proved tougher to crack than CEOs, owing in part to long-established relationships between the NRA's powerful lobbying arm and lawmakers in places like Missouri.

NRA lobbyists are a "regular presence" in the state's legislative chambers, said Stacey Newman, a Democratic state representative from the St. Louis suburbs. "We have a gun bill every year," she said. "It's no secret where these ideas come from."

South Carolina, North Carolina and Georgia all recently approved new laws that allow concealed weapons in bars, following big pushes by the NRA. Some version of open carry is permitted in 40 states.

Kristin Goss, a Duke University political scientist who has researched the politics of gun reform for a decade, said the NRA's might isn't just financial. Gun rights supporters are enthusiastically engaged. "They have an aura of invincibility that the other side doesn't have," Goss said.

Even in reliably blue states, there are worries that votes for gun restrictions can be hazardous. In Connecticut, Democratic Gov. Dannel Malloy is locked in a neck-and-neck fight for re-election, a year after he signed one of the toughest gun control laws in the country. (Malloy only narrowly won his office in the first place).

"For elected officials to take gun regulations seriously, especially in red or purple states, there has to be evidence that officials can vote for moderate gun control measures and survive," Goss said.

Bloomberg's initial approach to this conundrum was to declare war. "We've got to make them afraid of us," he said of lawmakers who didn't support reasonable gun restrictions like background checks.

In August, Bloomberg's political action committee invested $150,000 in ads to unseat Sheriff David Clarke, of Milwaukee County, Wisconsin, who had urged people to arm themselves because "simply calling 911 and waiting is no longer your best option." Clarke survived the challenge, and later told Fox News that the public "was put off by" Bloomberg's involvement.

The endorsement campaign that rolls out this week seems to consciously chart a safer, less confrontational course. The two Moms Demand Action ads released so far are simple, but emotionally powerful testimonials in support of candidates who support the types of gun restrictions, such as background checks, that polls consistently show are backed by most Americans.