At last month's first Democratic primary debate, gun control emerged as one of the hottest topics of the evening, in light of major mass shootings that occurred earlier that month. If the dialogue around gun control during the debate proved anything, it's that the issue isn't as simple as being "pro-gun" or "anti-gun." Unlike their Republican counterparts, the current Democratic candidates on gun control predominantly agree on the necessity of background checks, but their stances on some other factors — like open-carry, gun-show loopholes, and waiting periods — differ slightly. These slight differences could once again emerge as a major point of contention, as they were for Clinton and Sanders last month, in the next Democratic debate this Saturday.

In case the scary fact that many mass shooters legally obtained their firearms doesn't speak for itself, you should know that all of the factors that determine who gets to obtain what kind of gun and how this should be regulated can have tremendous consequences. Due to funding and lobbying by the NRA, Republican candidates would rather blame and miscast the mentally ill as violent (or in Bobby Jindal's case, blame single mothers and abortion rights), than blame the loose gun control policies in many states that enable people to easily and legally obtain firearms. However, Democratic candidates Hillary Clinton, Bernie Sanders, and Martin O'Malley have all come forward with their own reasonable gun control policies. Here they are, ranked.

1. Martin O'Malley

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O’Malley advocates for universal background checks, strongly opposes Internet sales of firearms, and has also vocally called for a 21-year age minimum for gun purchases. Like Sanders and Clinton, O'Malley opposes allowing individuals with domestic abuse and other criminal histories being allowed to own weapons.

As early as 2000, O'Malley adopted a manifesto listing ideas to make America "the safest country in the world" through "[making] it possible to disable and/or trace guns used by unauthorized persons." On his campaign website, O'Malley also calls for fingerprint-based license, the completion of safety training for gun buyers, waiting periods, and concealed carry.

O'Malley differs with Sanders in opposing the Protection of Lawful Commerce in Arms Act, which prohibits liability lawsuits from being brought against gun manufacturers and dealers based on the criminal misuse of firearms. In fact, O'Malley went so far as to invite Lonnie and Sandy Phillips, the parents of a victim in the Aurora theater shooting, to attend the Democratic debate with him. The couple had sued the ammunition dealer that sold to the shooter. The Phillips lost the case, and owe more than $203,000 to the company.

O'Malley's platform on gun control lacks the controversial Senate votes of Bernie Sanders that have disappointed some progressives, and unlike Clinton, he has never come out on the record vocally supporting gun rights and upholding the second amendment. All candidates maintain common sense stances that would very possibly make tragic mass shootings less frequent, but O'Malley's gun control record and stances currently appear to be the strictest.

2. Hillary Clinton

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Like her Democratic rivals, Hillary, too, is a strong proponent for background checks and banning gun sales to domestic abusers and criminal offenders. Clinton has also come out strongly against the gun show loophole, and even talked about utilizing executive power to regulate this, according to her campaign. Unlike Sanders, Clinton voted against the Protection of Lawful Commerce in Arms Act.

"It's time the entire country stood up against the NRA," Clinton said, impressively raising the dialogue about gun control at last month's debate. Clinton has also come out as willing to look into the "Australian model" on gun control, which, in her own words, was able to set a different standard for gun purchases and "curtail supply" by "offering to buy back those guns."

However, as The Washington Post points out, in 2008, Clinton herself was a supporter of gun rights and the second amendment, referencing personal memories of learning to shoot with her father. "You know, some people now continue to teach their children and their grandchildren. It’s part of culture. It’s part of a way of life. People enjoy hunting and shooting because it’s an important part of who they are," Clinton stated. Analysts at the time believed that her defense of gun rights was a response to a negative remark by then Senator Obama about Americans' tendency to "cling" to guns and religion.

3. Bernie Sanders

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Sanders is an advocate for stronger background checks and banning semiautomatic guns and assault weapons. The Vermont senator, whose pro-hunting state is notoriously lax about gun control, has stated that while he supports hunters, he "doesn't believe that hunters need assault weapons and AK-47s to kill deer."

The controversy with Sanders' gun control stances lies with his voting record on the Brady Bill, which mandates background checks and waiting periods, and the Protection of Lawful Commerce in Arms Act.

When questioned about his multiple votes against Brady Bill at the last debate, Sanders cited his stance against the bill's gun show loophole, which refers to a clause in the bill that allows sales of firearms by private sellers, including those done at gun shows. However, Sanders has remained ambiguous about his stance on crucial waiting periods in gun sales, which the Brady Bill mandates.

Sanders also voted for the Protection of Lawful Commerce in Arms Act in 2005. He clarified at last month's debate:

Do I think that a gun shop in the state of Vermont that sells legally a gun to somebody, and that somebody goes out and does something crazy, that that gun shop owner should be held responsible? I don't. On the other hand, where you have manufacturers and where you have gun shops knowingly giving guns to criminals or aiding and abetting that, of course we should take action.

Sanders did place emphasis on the word "legally" when discussing the sale of a gun later used for violence, but Clinton made a valid point at the last debate by arguing that Sanders' stance granted the gun industry immunity and simply did not hold gun manufacturers accountable. Ultimately, compared to his rivals' much harsher gun control track records, Sanders' gun-related leanings that favor hunters and gun shops are a disappointment to some progressives and Democratic voters.