The passion of gun owners has met the passion of protective moms in the fight over firearms restrictions, which will intensify this week as President Barack Obama delivers his State of the Union address.

Against all odds, a coalition that includes suburban moms, religious leaders, mayors and long-embattled gun safety lobbyists has set out to neutralize the grass-roots power of the 4.5 million-member National Rifle Association. It’s a tall order, but gun safety groups say they’ve drawn money and members since the December mass shooting at Sandy Hook Elementary School in Newtown, Conn.

Obama will promote his gun safety agenda in his annual address to Congress on Tuesday, the first time in more than a decade that the State of the Union will tackle the emotional topic of guns. His new grass-roots advocacy group, Organizing for Action, is also urging its members to mobilize behind the president’s agenda, which includes a ban on military-style assault weapons and universal background checks for gun purchasers.

Gun safety advocates plan rallies and news conferences Monday in at least a dozen congressional districts. The activists will urge key lawmakers they view as persuadable on the issue to support the president’s gun proposals.

“Intensity matters a lot, and right now we have it,” said Mark Glaze, director of Mayors Against Illegal Guns, a coalition of 850 mayors backed by New York’s Michael Bloomberg. “The public sentiment, including among gun owners, to do everything we can to fix this problem is as high as it’s been in a generation.”

Mayors Against Illegal Guns will bring some 100 gun violence survivors to Capitol Hill this week to lobby members of Congress. The group ran a $100,000 ad during the Super Bowl. Also this week, a new advocacy group and super PAC founded by former Rep. Gabrielle Giffords, D-Ariz., and her husband, Mark Kelly, will unveil a TV ad with a gun safety message. The PAC reportedly aims to raise $20 million this year.

Another Bloomberg-backed PAC, Independence USA, has unleashed more than $600,000 worth of ads attacking Democrat Debbie Halvorson, a congressional candidate in the special primary in the Illinois 2nd District, for her past NRA support.

At the opposite end of the spectrum, One Million Moms for Gun Control, a shoestring group started by a mother of four in suburban Indianapolis, will paper Capitol Hill Thursday with anti-gun “Have a Heart” valentines handmade by children.

“We are creating social-media campaigns that really motivate and mobilize moms through emotion, because that is how we are driven: by a desire to protect our children,” said the group’s founder, Shannon Watts. Watts said her group is applying for tax-exempt status but is operating for now on a zero budget with the pro-bono help of a handful of moms with legal and public relations expertise.

Such homespun efforts are up against an NRA budget that topped $243 million in 2010, tax records show. By contrast, the Brady Campaign to Prevent Gun Violence reported spending $3.1 million that year. The NRA’s PAC spent more than $16 million in the 2012 elections.

The gun rights group’s success derives in part from member loyalty built through such initiatives as gun training and shooting clubs, said James Thurber, director of American University’s Center for Congressional and Presidential Studies. By contrast, he noted, gun safety advocates can’t offer tangible services, which partly explains their lackluster budgets and membership in recent decades.

“There’s no sustained organization out there that gives the people something other than feeling good about trying to get rid of guns,” Thurber said. “They’re not getting together weekly to do something, like the [pro]-gun people. And so therefore, it’s very hard to sustain those kinds of things.”

But the deaths of 20 children and six school staff members in Newtown changed everything, gun safety activists argue. One Million Moms for Gun Control has rallied tens of thousands of members and set up 80 chapters nationwide in the eight weeks since its launching, Watts said. She said her group, which is not related to the group that mounted an anti-gun “Million Mom March” in Washington in 2000, is patterned after Mothers Against Drunk Driving.

The Brady Campaign to Prevent Gun Violence has seen its membership soar from fewer than 200,000 in 2012 to between 500,000 and 1 million now, said its president, Dan Gross. The group’s budget this year will be in the $10 million range, almost twice last year’s. The group is gearing up to expand its Washington presence, said Gross.

The NRA press office did not return calls seeking comment. The organization has gained at least 250,000 new members in the weeks since the Newtown shooting and has rejected new gun restrictions in favor of improved mental-health services and armed guards at schools.

Several progressive groups that do not have a single-issue gun focus also are organizing for new firearms restrictions. These include Americans United for Change and the Progressive Change Campaign Committee, which has released gun-focused ads and polls targeting Senate Minority Leader Mitch McConnell, R-Ky.

“There’s a hard-core base of NRA supporters that are kind of fanatical on this issue; they are single issue voters,” said Ladd Everitt, director of communications for the Coalition to Stop Gun Violence, another gun safety group staging events aimed at members of Congress this week. “That’s what we need to match, and we’ve known it for some time. The difference is, in the wake of Newtown, we can match it now. Because the energy is off the charts.”