(AP Photo/Ricardo Moraes)

Six months after the shootings in Newtown, and one month after the Manchin-Toomey gun control legislation died in the Senate, we already have a test case of how the gun control might play out with voters. It has emerged this week as a major issue in the the special election for John Kerry’s vacated Massachusetts Senate seat—and the Republican candidate’s somewhat comical inability to effectively defend his position is perhaps a promising sign for reformers.

Last week, Representative Ed Markey, the Democratic candidate, released a fairly standard campaign ad promising to “fight for common sense laws to stop gun violence.” It noted that the Republican candidate, former Navy SEAL Gabriel Gomez, “is against banning high-capacity magazines like the ones used in the Newtown school shooting.” Watch:

Gomez and the national Republicans flipped out. “Exploiting a tragedy for political gain is sick,” Gomez said in a statement Friday. “Disgusting, Deplorable and Desperate Attack Ads on Former Navy SEAL Par for the Course for Markey,” tweeted the National Republican Senatorial Committee.

Gomez doubled down on this defense today, releasing an ad attacking “dirty Ed Markey,” and making an unusually explosive, and fact-stretching, claim: “Now, Markey actually blames Gomez for the Newtown shooting.” Watch:

It’s fair to say that Gomez is playing loose with the truth here. “Despite what the ad says, Markey has not blamed Gomez for the Newtown shooting,” The Boston Globe had to explain in a straight news story.

Gomez’s over-reaction suggests awareness of serious vulnerability on this issue. And what’s his actual response? He’s not debating a policy point—not attempting to explain why he opposes a ban on high-capacity magazines—but haphazardly trying change the conversation with an inflammatory attempt to play the victim.

His failure to conjure a sensible, post-Newtown argument against better gun laws might be an important tea leaf for the 2014 midterms, as well as the ultimate future of real gun legislation.

It’s useful to recall where the political debate stands. After comprehensive gun-control legislation died in the Senate last month, polls showed that senators who helped kill the bill faced plummeting approval numbers, while those that stood up for the legislation received notable boosts. Since 90 percent of the public favored expanded background checks for gun sales, this dynamic wasn’t very surprising, and it left reformers with two paths forward.

The first was to immediately try to take another bite at the apple: pressure key holdouts like Senators Kelly Ayotte and Jeff Flake to come back to the table, and try to pass a moderated version of the Manchin-Toomey legislation as soon as it became feasible. There have been some whispers about that possibility, but nothing concrete seems to be happening.

The other (not mutually exclusive) approach is to let the public fury build over the next eighteen months and use it as a weapon in the midterm elections. A vote allowing criminals to have guns is a good wedge to separate Republicans from moderate suburban voters, and if the Manchin-Toomey vote helps cost some members their seats, a humbled 114th Congress could take another swing at gun control legislation

This strategy has the added virtue of potentially tougher legislation: instead of having to modify the already weakened Manchin-Toomey bill (bans on assault weapons and high-capacity magazines were dropped early on, and a large background check exemption for private sales was added at the eleventh hour), reformers could start all over with a much better package.

Markey’s ad is a perfect example of this latter approach: not only is he hitting his opponent for opposing popular gun control legislation, but he’s widening the debate past Manchin-Toomey, and focusing on assault weapons and large clips. (Gomez, to his credit, has repeatedly backed Manchin-Toomey and expanded background checks, leaving assault weapons and high-capacity clips as the major area of distinction.)*

Gomez's response wasn't to defend a position against high-capacity clips, but rather try to change the story. If gun control opponents can’t do any better than Gabriel Gomez at defending their policies, things are looking up for reform.

*This story has been updated to reflect the fact that Gomez supports Manchin-Toomey and closing the gun show loophole.

Walmart helped make the AR-15, which was the weapon used by Adam Lanza, the most popular assault weapon in America, George Zornick writes.