( CNN ) -- Sometimes it takes a tragedy to make us confront reality . In the wake of the slaughter of first graders in Newtown , Connecticut , there are signs that the country -- and Congress -- are ready to confront the cancer of gun violence that kills over 11,000 Americans each year . More than 200 Americans have been killed in mass shootings in the last five years . After each attack -- whether it was Virginia Tech or Aurora , Colorado -- we were told that it was too soon to talk about the role of guns . Now , the fever of denial might be breaking . A new Washington Post/ABC poll taken after the shooting shows that 54 % of Americans now support stricter gun laws and 59 % support a nationwide ban on high-capacity ammunition clips -- meaning those that contain more than 10 bullets . The big question of course is whether Congress will listen . This has not been an area where politicians have carved out a new chapter of profiles in courage in recent years . Instead , they have run away in the face of the lobbying power of the National Rifle Association . But in the past two days , two Southern Democratic senators with A-ratings from the NRA have broken ranks to say that it is time to begin a serious , civil and constructive conversation about remedies to mass gun violence -- including perhaps a reinstatement of the assault weapons ban and a restriction of high-capacity clips . West Virginia Sen. Joe Manchin -- who famously took aim at a cap and trade bill with a high-powered hunting rifle in a 2010 campaign ad -- told CNN 's Christiane Amanpour that the Newtown shooting `` changed me . ... I do n't know of anybody that goes hunting with an assault rifle . I do n't know people that need 10- , 20- , 30-round clips . '' Add to this chorus of conscience Virginia Sen. Mark Warner -- a fellow former governor and current senator . He told a local Richmond TV station : `` I believe every American has 2nd Amendment right -- the ability to hunt is part of our culture . I 've had an NRA rating of an A . But you know , enough is enough . I 'm a father of three daughters and this weekend they said , 'Dad , how can this go on ? ' '' These two senators are leaders of the centrist coalition , and their evolution on this issue matters . It is particularly well timed because Sen. Dianne Feinstein announced her intention to submit legislation to reinstate the lapsed assault weapons ban as well as ban `` big clips , drums or strips of more than 10 bullets . '' That bill would provide the substantive basis for a new round of reasonable restrictions on weapons that have little purpose other than to kill as many people as possible , as quickly as possible . To date , there are few Republicans who have newly embraced the need for new gun legislation . Rep. Peter King of New York and Sen. Susan Collins of Maine are influential , but among the few returning congressional Republicans who back the reinstatement of the assault weapons ban and restrictions on the sale of mass capacity magazines . But the senators who have boasted the backing of the NRA in the past have been notably silent since the slaughter in Newtown . That can fairly be read as a hope that this moment will pass . New York Mayor Michael Bloomberg , an independent , has been leading the gun crusade in recent years through his group Mayors Against Illegal Guns . In many areas , America 's mayors have been leading the policy debate in our nation , and this organization 's message has taken on new urgency , unveiling an effort to encourage supporters to `` Demand a Plan '' from Washington . In the wake of the Newtown shootings , nine new mayors decided to join the group , including the mayors of Raleigh , North Carolina , and Tucson , Arizona -- major cities in the heart of gun country , the South and West . In this and so many other areas , the fact is that Americans are less polarized than our politicians . A poll commissioned by Mayors Against Illegal Guns and conducted by conservative pollster Frank Luntz found that 74 % of NRA members supported background checks on every gun sale . The larger point is that there is common ground to be found even on this emotional issue -- especially if mental health is part of the civic conversation , because self-control and gun control are intertwined . There is a responsibility to remember after events like this -- a need for sustained focus after the heat of the moment passes . Real change will require constructive civic conversation , the kind that Manchin noted has become rare , saying : `` It 's a shame that we 've gotten so toxic a political environment that today in Washington that you ca n't sit down and have reasonable discussions with reasonable people to come out to reasonable conclusions . '' But there is a moral urgency to follow through on this moment . The normal politically convenient amnesia ca n't be allowed to set in . More senators need to be pressed on the issue of reasonable restrictions and prodded by the polls . Feinstein 's proposed bill will no doubt start a substantive debate . As President Obama said in his memorial address in Newtown , `` No single law , no set of laws can eliminate evil from the world or prevent every senseless act of violence in our society . ... But that ca n't be an excuse for inaction . '' The opinions expressed in this commentary are solely those of John Avlon .
John Avlon : The horrific shootings in Newtown changed debate on guns . He says several pro-gun Democrats have spoken out for new controls . Avlon : A poll shows a boost in public support for gun control . There is a moral urgency to follow through on this moment , he says .