The dark reason why guns are virtually guaranteed to be a major issue of the 2016 campaign

After years of ducking presidential-campaign battles over gun laws out of fear of the powerful gun lobby, it appears that Democrats are finally ready to go on the offensive.

Increasingly, Democrats are becoming more and more outspoken about gun violence in the wake of seemingly ever-increasing mass shootings, despite the fact that the American public remains as opposed as ever to many gun-control measures.

Democratic presidential front-runner Hillary Clinton set the tone early in her campaign after a mass shooting at an historically African-American church in Charleston, South Carolina. And she has become much more vocal in her calls for stricter gun laws, making it a recurring feature in her stump speeches.

"This is a controversial issue. I am well aware of that. But I think it is the height of irresponsibility not to talk about it," Clinton said this week, according to The Washington Post.

Clinton's increased calls for gun control mirror President Barack Obama's recent shift to re-focus on gun laws in the wake of a slew of mass shootings. In addition to the Charleston incident, there have been high-profile mass shootings at military facilities in Tennessee and at a movie theater in Louisiana.

Obama has labeled the failure of Congress to pass new gun laws the biggest frustration of his tenure. He has spoken out multiple times recently on the subject, including after the Charleston shooting that killed nine people.

"I've had to make statements like this too many times," Obama said in a statement from the White House. "At some point, we as a country will have to reckon with the fact that this type of mass violence does not happen in other developed countries."

This is a major shift from 2008, when both Clinton and Obama were criticized for failing to talk about the issue. During the heat of the 2012 campaign, Obama was reluctant to bring up the topic of guns even after the mass shooting at a Colorado movie theater. Passing gun-control measures, Democrats have long argued, had helped lead to Democrats overwhelming losses in the 1994 midterms that swept Republicans into power in Congress.

The new focus, then, is an interesting political calculus - because many signs actually show that Americans' support for gun rights is growing.

A widely-cited Pew study published in December showed that support for gun rights has surpassed Americans' support for gun control, though some analysts have pointed out that the phrasing of Pew's question might have led more Americans to appear friendlier to guns.

Gun-rights advocates have also experienced success in state legislatures, beyond helping to block Democrats' federal legislation that would have expanded background checks on gun purchases. In almost three years since the Sandy Hook Elementary massacre in Newtown, Connecticut, 70 of 109 state gun laws have actually loosened restrictions, according to The New York Times.

But gun-safety groups say that below the surface, there is growing support for certain goals.

Citing broad support for background checks and a few legislative wins in the 2014 midterm elections, Everytown - the group co-chaired by former New York City Mayor Michael Bloomberg - argues that opposition to gun-rights groups like the National Rifle Association is much more organized and motivated even than it was in 2008 when Clinton last ran for president.

"Previously, people talked about an intensity gap, that, 'Yeah, everybody agrees, but this isn't anybody's No. 1 issue,' and we've seen that change dramatically in the last few years because of the big events and the ones that don't make as much news," Erika Soto Lamb, Everytown's communication director, told Business Insider.

Lamb acknowledged that in the past, gun-rights groups have scared lawmakers into silence. Now, she said, high-profile horrific shootings have forced candidates to talk about the dangers of guns more more frequently.

"I worked here in 2012, and I know how hard it was to get the candidates to address gun violence," Lamb said. "The candidates have been talking about guns far more than they did then."

But if increasingly strong rhetoric from Clinton and financial backing from Bloomberg worries gun-advocacy groups, it doesn't show.

Larry Pratt, Executive Director of Gun Owners of America, gave a reminder that President Bill Clinton himself admitted that threatening gun rights can be a perilous issue politically.

"Hillary Clinton is repeating the error her husband made in 1994 - pushing for gun control legislation. He realized his mistake and said so," Pratt told Business Insider. "Hillary is so ideological that she seems oblivious to the reality of gun control politics. She seems doomed to repeat her husband's political error."

For their part, Republican candidates aren't backing down and have argued that if more citizens were armed, more mass shootings could be prevented.

That's former Texas Gov. Rick Perry's (R) line - he railed against "gun free" zones on Sunday, suggesting that a well-trained citizen with a gun could've stopped the Louisiana movie-theater shooting.

Former Arkansas Gov. Mike Huckabee (R) has also embraced this argument. Following the Connecticut shooting that left 20 children and six others dead in 2012, Huckabee wrote on Facebook that not all victims of shootings want stricter gun laws imposed, pointing to a survivor of a mass shooting who now advocates for more relaxed gun laws.

Other candidates have tried to use shootings to remind voters of where they stand on certain issues.

That's what former Pennsylvania Sen. Rick Santorum (R) did following the Charleston shooting, claiming that the shooting was part of a larger attack on religious freedom. Sen. Rand Paul (R-Kentucky), meanwhile, said that even in the wake of a tragedy, government is not the answer.

"There's a sickness in our country. There's something terribly wrong. But it isn't going to be fixed by your government. It's people straying away, it's people not understanding where salvation comes from," Paul said.

But mass shootings, which tend to dominate news cycles, are occurring more and more frequently.

As Mother Jones points out, the number of days between mass shootings has dropped dramatically in recent years, from 220 between 1995 and 2005 to 99 between 2005 and 2015.

There are 467 days until Election Day.