Over the last four presidential elections, gun control has been as settled as any political question, with Democrats all but conceding the issue to Republicans in national elections. A spate of mass shootings during the first four years of the Obama presidency didn't change this, but there is some reason to think that the terrible elementary school shooting in Newtown, Connecticut could be different.

Gun control optimists shouldn’t count on Newtown to produce a sea change in public opinion. Pew Research, Washington Post, and CNN surveys each found that support for gun control held relatively stable and beneath 50 percent in the immediate aftermath of the Gabrielle Giffords and Aurora, Colorado shootings. Although mass shootings, like Columbine, have led to an increase in public support for gun control in the past, even this proved temporary, with public opinion returning to pre-Columbine levels within a year, as this chart from Mark Blumenthal shows:

But even though the public might not overwhelmingly favor gun control, there’s reason to believe that Democrats can again feel comfortable fighting for gun control after a decade of keeping it on the back-burner. After all, they're less reliant on rural, gun-owning voters than at any time in the history of the party.

Democrats backed away from gun control after concluding that the issue cost Al Gore the presidency, since he lost conservative, pro-gun states carried twice by Bill Clinton, like Ohio, Arkansas, West Virginia, or Missouri. But although national Democrats stayed silent on the issue for the next four presidential elections, neither John Kerry nor Barack Obama reclaimed these conservative, pro-gun Clinton-Bush voters. In fact, Obama and Kerry both performed worse than Gore among conservative rural voters. The fact is that these pro-gun voters are lost to Republicans, and probably for good.