Bloomberg: I'm coming after the NRA

A U.S. Park Police helicopter removes a man from the Washington Navy Yard on September 16, 2013. At least 12 people were killed in a shooting rampage, according to Washington Police Chief Cathy Lanier.

Connecticut State Police evacuate children from Sandy Hook Elementary School in Newtown, Connecticut, on December 14, 2012. Adam Lanza opened fire in the school, killing 20 children and six adults before killing himself. Police say he also shot and killed his mother in her Newtown home.

James Holmes pleaded not guilty by reason of insanity to opening fire July 20, 2012, at the Century Aurora 16 theater in Aurora, Colorado, during the midnight premiere of "The Dark Knight Rises." Twelve people were killed and dozens were wounded. Holmes is charged with 142 counts, including first-degree murder. His trial is scheduled to begin in February 2014.

A military jury convicted Army Maj. Nidal Hasan on Friday, August 23, 2013, of 13 counts of premeditated murder in a shooting rampage at Fort Hood, Texas. During the November 5, 2009 shooting, 13 people died and 32 were injured.

Jiverly Wong shot and killed 13 people at the American Civic Association in Binghamton, New York, before turning the gun on himself on April 3, 2009, police say. Four other people were injured at the immigration center shooting. Wong had been taking English classes at the center.

Pallbearers carry a casket of one of Michael McLendon's 10 victims. McLendon shot and killed his mother in her Kingston, Alabama, home, before shooting his aunt, uncle, grandparents and five more people. He shot and killed himself in Samson, Alabama, on March 10, 2009. McClendon left a note saying he put his mother "out of her misery."

Virginia Tech student Seung-Hui Cho went on a shooting spree on the campus in Blacksburg, Virginia, on April 16, 2007. Cho killed two people at the West Ambler Johnston dormitory and, after chaining the doors closed, killed another 30 at Norris Hall, home to the Engineering Science and Mechanics Department. He wounded 17 people before killing himself. It is the deadliest shooting rampage in U.S. history.

Mark Barton walked into two Atlanta trading firms on July 29, 1999, and fired shots, leaving nine dead and 13 wounded, police say. Hours later police found Barton at a gas station in Acworth, Georgia, where he pulled a gun and killed himself. The day before Barton had bludgeoned his wife and his two children in their Stockbridge, Georgia, apartment, police say. The children's birth mother and grandmother had been murdered six years earlier in Alabama. Barton was questioned but never charged in that crime.

Eric Harris, left, and Dylan Klebold entered Columbine High School in Littleton, Colorado, on April 20, 1999, armed with bombs and guns. The students killed 13 and wounded 23 before killing themselves.

George Hennard crashed his pickup through the plate glass window of Luby's Cafeteria in Killeen, Texas, on October 16, 1991, before fatally shooting 23 people and committing suicide.

James Huberty shot and killed 21 people, including children, at a McDonald's in San Ysidro, California, on July 18, 1984. A police sharpshooter killed Huberty an hour after the rampage began.

Prison guard George Banks is led through the Luzerne County courthouse in 1985. Banks killed 13 people, including five of his children, in Wilkes-Barre, Pennsylvania, on September 25, 1982. He was sentenced to death in 1993 and received a stay of execution in 2004. His death sentence was overturned in 2010.

Officers carry victims across the University of Texas at Austin campus after Charles Joseph Whitman opened fire from the school's tower, killing 16 people and wounding 30. Police officers shot and killed Whitman, who had killed his mother and wife earlier in the day.

Howard Unruh, a World War II veteran, shot and killed 13 of his neighbors on September 5, 1949, In Camden, New Jersey. Unruh barricaded himself in his house after the shooting. Police overpowered him the next day. He was ruled criminally insane and committed to a state mental institution.

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• Writers: 90% of Americans, 80% of gun owners want background checks for guns


• Writers: Sensible gun laws fail because of politicians' irrational fear of the NRA


• Writers: Everytown for Gun Safety group will show you can support gun control, win elections


• Michael Bloomberg, Shannon Watts: The gun lobby no longer has the field to itself

Editor's note: Michael Bloomberg is the former mayor of New York City and co-founder of Mayors Against Illegal Guns. Shannon Watts is the founder of Moms Demand Action for Gun Sense in America, which she started after 26 people, 20 of them children, were shot to death at Sandy Hook Elementary School in Connecticut in December 2012.

(CNN) -- A year ago on Thursday, the U.S. Senate failed to pass a bill that would have helped fix our nation's gun laws by requiring background checks on all purchases of firearms. Ninety percent of all Americans -- and more than 80% of gun owners -- believe that all people should be subject to such checks. And even though the bill won majority support in the Senate -- more than 50 members -- it was not enough to break a filibuster.

But in the year after the massacre at Newtown, Connecticut, on December 14, 2012, the grassroots movement to pass common sense gun laws and policies that are consistent with the Second Amendment has made great progress just about everywhere except Washington.

In Colorado, Connecticut, Delaware and New York, local citizens helped lead the successful push for legislation that closed loopholes in background checks laws. In Washington state and Wisconsin, citizens helped pass laws that keep firearms out of the hands of convicted domestic abusers.

In Colorado alone, the new law stopped more than 160 prohibited buyers from getting their hands on a gun, and as Coloradans know too well, it only takes one to devastate a family, a community, a nation. And the law hasn't gotten in the way of law-abiding gun owners, who bought more firearms in 2013 than in any preceding year.

We also gave voice to hundreds of thousands of Americans who persuaded Facebook and Instagram to change their policies so that unlicensed gun sellers cannot use their sites to sell guns without background checks.

Thousands marched in Washington for gun control in January last year after the Sandy Hook school murders.

Moms for Gun Safety ran this ad, questioning why a type of chocolate is banned to protect kids but not assault weapons.

These significant victories were won by a growing, nonpartisan coalition that is refusing to wait for Washington to act. That coalition includes parents, mayors, police chiefs, religious leaders, gun owners and everyday Americans of all political persuasions. Mothers, in particular, have been at the forefront of this fight. They've given testimony at town halls, led "Stroller Jams" at state capitals, hosted quilting bees and delivered petitions to legislatures and companies across the country.

To unify the efforts of this diverse coalition of Americans, we are launching Everytown for Gun Safety in America, a new umbrella organization that will be the largest and best-organized counterweight to the gun lobby that has ever been created. Everytown for Gun Safety will expand on the work of two existing organizations -- Mayors Against Illegal Guns and Moms Demand Action for Gun Sense in America -- and take the fight for gun violence prevention policies to every community in the country.

Everytown for Gun Safety will continue pushing for better background check laws in Congress and state houses. But we will also broaden our focus to include other issues that are important to Americans, like safe storage education campaigns to help keep kids from being killed by unlocked or dangerously stored guns. And new laws to keep guns out of the hands of domestic abusers. And efforts to help reduce the nearly 19,400 suicides that happen every year with guns.

In each area, we will make progress by doing something that no gun group, other than the National Rifle Association, has ever done: inform and mobilize voters. The reason the NRA has political influence -- in addition to its campaign contributions -- is that it has scared elected officials into believing that voters will oppose them unless they follow the NRA's Washington leadership, which has grown increasingly extreme and increasingly out of touch with its own members.

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In fact, the NRA's reputation for political strength is wildly blown out of proportion and the election results from three statewide contests in Virginia this past November reflect that reality. Candidates who spoke out in support of common sense gun violence prevention policies were elected as governor, lieutenant governor, and attorney general. In the attorney general's race, his campaign manager said that the candidate's support for sensible stances on gun issues was a major factor in his victory.

Nonetheless, the perception of an unbeatable gun lobby still lingers and part of our mission will be showing candidates and elected officials that the vast majority of Americans and gun owners support common sense gun policies that respect the Second Amendment and save lives.

To mobilize voters who are committed to backing candidates that support common sense gun policies, Everytown for Gun Safety is launching a Gun Sense Voter campaign. Before the 2014 midterms, we aim to get at least 1 million Americans to pledge to vote for state and federal candidates based on where they stand on gun safety. We'll keep voters informed by tracking candidates' positions and determining which of them support gun safety and which do not.

Leaders from all walks of life will join us on our board of directors, including one of our nation's most respected military leaders, Adm. Mike Mullen, former chairman of the Joint Chiefs of Staff; University of Oklahoma president and former Sen. David Boren; and former Secretary of Homeland Security Tom Ridge. All of us are united by the belief that accepting the status quo -- 12,000 Americans are murdered with guns every year -- is unconscionable.

There is no doubt that we have a big hill to climb. Well-funded, entrenched special interests are always difficult to defeat. And for years, the gun lobby has largely had the field to itself. No longer.

Everytown for Gun Safety and its growing grassroots network will be gunning for change that both protects our country and respects our Constitution.

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