Phoenix, AZ (written by David Rookhuyzen/Arizona Republic) -- Ellen Davis' cause comes down to two numbers: 100 and 80,083.
The first is the number of bullets James Holmes, the suspect in the movie-theater shooting in Aurora, Colo., is reported to have fired in the first minute of a rampage that left 12 dead and 58 wounded.
The second is the number of people who have joined Davis in her attempt to prevent another mass shooting.
Davis, a Phoenix-area lawyer and mother, started an Internet petition to reinstate the 1994 federal ban on assault weapons that expired in 2004. After three weeks, her petition has garnered about 80,000 signatures from across the country.
Shocked at reports that Holmes used an AR-15 semi-automatic rifle with a 100-round drum magazine, Davis said her thoughts went to her 21-year-old son, who had been in a Phoenix-area theater that same night. On July 20, the same day as the tragedy, she started her petition.
The effort is adding hundreds of names a day, and the response is surprising, she said. Davis expected a few family members and friends to sign, but the groundswell of support has convinced her that reinstating the ban can be done.
"The fact that I got 75,000 signatures says to me this is a possibility," she said.
Davis said she is not against individuals having guns, but assault weapons are such a risk to society that they need to be controlled.
She pointed out that Jared Loughner, who killed six and wounded 13, including then-Rep. Gabrielle Giffords, near Tucson last year, was wrestled to the ground when he had to reload his 15-round Glock handgun.
"What if he had 100 rounds?" Davis said.
Davis plans to e-mail her newly found base and organize a letter-to-the-editor campaign to spread the message, she said. Her goal is to start a grass-roots movement and eventually find someone to sponsor the initiative in Congress.
Even if that doesn't happen, she just wants to start a dialogue, she said.
"I'm tired of being silent. Too many have died," Davis said.
A Gallup poll from last November found 43 percent of Americans in favor of the assault-weapons ban and 53 percent opposed. A Pew poll conducted after the Aurora shooting found 47 percent of Americans in favor of gun control and 46 percent in favor of protecting gun ownership.
In the wake of high-profile shootings in Arizona, Colorado and Wisconsin, the climate could be right for gun-control advocates.
Three Tucson-area shooting victims were featured in a television ad that began running this week as part of the Demand a Plan campaign. The movement, spearheaded by the nonpartisan Mayors Against Illegal Guns, calls on President Barack Obama and presidential candidate Mitt Romney to address how they will confront gun violence in America.
Demand a Plan, started after the Aurora shooting, took out a full-page ad in USA TODAY on July 25 and recieved more than 125,000 petition signatures on its website by Tuesday, a media release said.
Ladd Everitt, a spokesman for the Coalition to Stop Gun Violence, said that, in the wake of recent mass shootings, the calls for tighter gun control his organization has seen via e-mail and social media have reached unprecedented levels. The challenge now is keeping that energy and intensity so politicians notice, he said.
"If we can sustain it, we can win," Everitt said.
Daniel Vice, senior attorney for the Brady Center to Prevent Gun Violence, said Davis' petition is part of a building movement that is similar to the outcry that led to the ban during the Clinton administration. A sign that this isn't a quick-fading national mood is the gun-control questions being asked of both presidential campaigns, he said.
"People are starting to realize how dangerously weak our gun laws are," Vice said.
Critics, however, doubt the renewed effort, including reinstating the assault-weapons ban, will get far.
Alan Gottlieb, founder of the Second Amendment Foundation, described the 1994 ban as a "feel-good nothing" law that was based on a gun's appearance instead of actual criteria such as caliber. Even then, the bill passed by one vote, which was wrangled by including the 10-year expiration provision, he said.
Constitutional issues aside, a stricter ban would be impractical, Gottlieb said. The AR-15 and the handgun used in the Tucson-area shooting are popular, he said. Plus, Congress is more pro-gun now than in the 1990s, he said.
"It's just not going to happen," Gottlieb said.
He said calls for stricter control also ignore the up to 2 million incidents a year in which would-be victims defend themselves with guns. In 98 percent of those cases, the gun isn't even fired, he said. "To make good public policy, you have to look at both sides of the issue," Gottlieb said.