December 14, 2012, is a day that will forever be etched in Shannon Watts’ memory.

That day, she awoke to the heartbreaking news that gunman Adam Lanza had murdered his mother before going on a shooting rampage at Sandy Hook Elementary School in Newtown, Conn., killing 20 children and six adults.

The nation had seen mass shootings before. That very summer, 24-year-old James Holmes opened fire in a crowded theater in Aurora, Colo., killing 12 people and injuring 58 others. In April 2007, Virginia Tech student Seung-Hui Choi murdered 33 people and injured 23 on campus. Cries for more gun control were heard each time. Those cries were indeed loud but soon faded.

When the Newtown massacre happened, something changed. The cries for gun control grew louder. And this time around, they are refusing to fade away.

Watts, a mother of five from Zionsville, a suburb of Indianapolis, Ind., sat down in her kitchen that very day and began working on a plan to ensure the lives lost in Newtown weren’t soon forgotten. She felt for the children who died that day. She understood the hurt of parents who lost their babies in the senseless killing officials are still trying to understand.

An unthinkable act of cruelty had unfolded once again in America, and Watts wanted to put an end it. She founded One Million Moms for Gun Control, a grassroots effort uniting mothers across America for one cause: the fight for tougher gun measures.

“[Sandy Hook] was the tipping point,” Watts said in a telephone interview. “It was an elementary school where six- and seven-year-old babies were shot, [some] 11 times each. I think as a country we had grown immune to these shootings. But not this time.”

Now six weeks in, what began as a Facebook page has more than 50,000 supporters and 75 local chapters nationwide. The organization has held more than a dozen events for the cause and has scheduled meetings with legislators. The movement brought out hundreds to walk across the Brooklyn Bridge and recently drew thousands for a march in Washington, D.C.

States have already begun to push legislation promoting tougher gun laws.

New York was the first since the Sandy Hook massacre to pass what is considered the toughest gun control law in the nation. Governor Andrew Cuomo signed the bill into law in mid-January with the aim of keeping guns out of the hands of the mentally ill, as Lanza is suspected to have been. The law also requires mental health professionals to report the risks if they have determined any gun owner is likely to cause harm.

California Democratic Sen. Dianne Feinstein has also introduced legislation to ban assault weapons, as they were from 1994 until 2004, and magazines with more than 10 rounds of ammunition.

At the highest level, President Barack Obama has issued executive actions that include mandating background checks for those who want to buy a gun and a ban on military-style assault rifles.

Some Second Amendment advocates see these actions as a nonstarter.

In a testimony Wayne LaPierre, executive vice president of the National Rifle Association, plans on delivering before the Senate Judiciary Committee on Wednesday, he will say the association is ready to participate in “a meaningful effort” to solving the gun problems. But LaPierre will be quick to add that “law-abiding gun owners will not accept blame for the acts of violent or deranged criminals. Nor do we believe the government should dictate what we can lawfully own and use to protect our families.”

“We need to be honest about what works and what does not work,” LaPierre’s testimony reads. “Proposals that would only serve to burden the law-abiding have failed in the past and will fail in the future.”

One Million Moms for Gun Control members will tell you they understand the Second Amendment gives Americans the right to bear arms. What they will argue is that not all types of weapons should be in the hands of ordinary citizens.

So they are calling for a common-sense solution to the emotionally charged debate. Watts and her supporters propose four things: that Congress mandate background checks for all gun purchases, a ban on assault weapons, regulating the trading of ammunition and, at the state level, addressing laws that allow the carrying of concealed firearms.

And they are prepared to fight any laws backed by the NRA in state legislatures. They also want to see Obama’s gun control proposals brought to the floor on Congress in one piece and passed.

“We are in this for the long haul,” Watts said. “This is not a short-term effort.”

Arriving at a bipartisan solution is sure to be an uphill battle. Any solution to the gun control debate will have to take into consideration the rights of the 4.2 million members the NRA boasts, but Watts is conscious of the momentum, and the numbers, behind the effort she leads.

“Women and mothers elected Obama, and we can do the same thing for gun control,” Watts said. “The rights of the few should not overcome the safety of the majority.”

A blueprint for her groups' action can be found in the successful work of a similar organization, Mothers Against Drunk Driving, or MADD. "We can change attitudes about guns," reads a comment on the organization's website. "It only takes will, determination and organization, the same ingredients that MADD uses."