“Bloomberg Backlash” is the phrase the Drudge Report is using in its headline about the recall of two state senators in Colorado over their votes to regulate guns. It’s a national story because it represents voters repudiating an anti-gun campaign Mayor Bloomberg is trying to extend across the country. In the gun debate, moreover, Colorado is not just any state. It was the one that saw, at Columbine and Aurora, two of the worst mass murders ever committed with guns in America. If any a state had reason to tighten gun regulations, an argument could be made, Colorado would be high on the list.

Colorado rushed out its new regulations in the wake of the massacre at Newtown, Connecticut. It passed laws to require background checks on private guns sales and limit the size of ammunition magazines. It did so over the objection of Republicans and as gun control measures were failing in the U.S. Congress. Voters, at least in some districts, were furious. One senator who was just recalled, Angela Giron, was from a working class district that was solidly Democratic. The other, John Morse, was president of the state senate. They had been key to passing the new gun restrictions in the Centennial State.

Mayor Bloomberg became an issue in Colorado because he personally invested $350,000 to defeat the recall. Something like $3 million was invested by left-wing groups in an attempt to salvage the careers of the two politicians. “It’s our election,” the New York Times quoted one voter as saying, “It’s not D.C. It’s not New York. It’s us.” The National Rifle Association, which also spent heavily in the recall, put out a statement pointing its finger at Bloomberg. The voters’ message, it said, was that the job of officials was to “to defend our rights and freedoms and that they are accountable to their constituents – not the dollars or social engineering agendas of anti-gun billionaires.”

What is it about Michael Bloomberg that infuriates people as far away as Colorado? It happens that we have a theory about this. It’s not that the mayor is so all-fired liberal or weird or even left-wing; he’s none of those things. It’s not even that background checks or limits on high-volume magazine are all that radical. The thing that stands out about Mr. Bloomberg is the gun control regime he countenances in his own city. Never mind big magazines. One can’t get a permit to carry even a single-shot pistol in New York City. Never mind background checks. Mother Theresa couldn’t get a permit to carry even the daintiest derringer in New York.

Our favorite example is Craig Whitney. He lives at Brooklyn and is now retired from the New York Times, where he exercised his First Amendment rights every day without once needing a permit. A Vietnam veteran who was trained to carry a pistol in the Navy, he is so irked that he needs — and can’t get — a permit to exercise his Second Amendment rights that he’s written a whole book about it. Coloradans are a lot of things, but stupid isn’t one of them. A sizable share of them are prepared to countenance some regulation of guns. But they can see where Mr. Bloomberg is going. And they don’t want to go there. They are not prepared to gainsay the Second Amendment entirely.

No wonder it’s being called the Bloomberg Backlash. The intriguing question is whether it could happen — or is already happening — here in the mayor’s home town. In the primary election this week, the most left-wing candidate, William De Blasio, floored the political establishment with the surge that appears likely to have secured him the top of the Democratic ticket in the campaign for the general election in November. He did it by contrasting himself with the other contenders and running as the anti-Bloomberg.

It would be inaccurate to suggest that guns were, at least on the face of it, a central issue in the campaign, and Mr. De Blasio did not run a pro-gun campaign. But he did run against a stop-and-frisk policing program designed to ferret out, among other things, illegal guns. Even for those of us who support stop and frisk, it’s not so hard to imagine that New Yorkers could eventually come to see stop and frisk as a question of not only the Fourth Amendment right to be secure against unreasonable searches, but also the Second Amendment right to bear arms. To those who think this is impossible, we commend the former president of the Colorado state senate.