Wednesday's deadly shooting in Charleston, South Carolina, was, for the president, a reminder that the U.S. has done little to curb gun violence, and he called on the U.S. to take action.
"Now is the time for mourning and for healing, but let's be clear: 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 advanced countries," Mr. Obama said Thursday. "It doesn't happen in other places with this kind of frequency and it is in our power to do something about it."
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But in the same breath, he anticipated the pushback from Congress, given its relative inaction after the 2012 shooting at a Newtown, Connecticut elementary school and he continued, "I say that recognizing the politics in this town foreclose a lot of those avenues right now."
Still, several candidates vying for the White House talked about what they thought should be done -- and the reaction has varied.
Here's a look at where the 2016 field stands on gun control legislation:
Here's what she had to say Thursday:
"How many innocent people in our country from little children to church members to movie theater attendees? How many people do we need to see cut down before we act?" Clinton asked a crowd of Latino political leaders in Las Vegas on Thursday. "As we mourn and as our hearts break a little more, and as we send this message of solidarity, we will not forsake those who have been victimized by gun violence."
Clinton further called for honesty in facing the "hard truths about race, violence, guns, and division" in America.
While her recent comments now align closely with those of President Obama's in the wake of the Charleston shooting, during the 2008 Democratic primary race against the then-Illinois senator, Clinton positioned herself to the right. In a televised primary debate that year, the Democratic candidate backpedaled from a proposal for a national gun registry she had made in 2000.
Democratic challenger Martin O'Malley sent a letter to supporters Friday about gun measures with the subject line "I'm pissed." He complained that after the tragedy in South Carolina, "instead of jumping to act, we sit back and wait for the appropriate moment to say what we're all thinking: that this is not the America we want to be living in."
He asked "how many senseless acts of violence in our streets or tragedies in our communities will it take to get our nation to stop caving to special interests like the NRA when people are dying?" And he attacked the NRA for "blaming the victims of yesterday's shooting for their own deaths, saying they too should have been armed."O'Mally called for a national assault weapons ban, stricter background checks and efforts to reduce straw-buying.
As Maryland governor, O'Malley asked the state for help to "further toughen the enforcement of our gun laws" in 2011. In 2013, he also signed into law an NRA-opposed gun bill that banned the sale of several assault rifles and broadened background checks.
After the 2012 Newtown massacre, then-Rhode Island Gov. Lincoln Chafee backed a state measure to ban semi-automatic assault weapons and high-capacity magazines.
The longshot Democratic presidential candidate has also voted against federal legislation that would have banned lawsuits against gun manufacturers -- a vote he took while he was still a Republican senator.
While Sanders falls to the left of Democratic frontrunner Hillary Clinton on many policy points, his voting record on gun control is mixed.
Vermont has long history of gun ownership, and as recently as 2010, over half the adults in the state owned guns, so it is not entirely surprising that Sanders has often sided with gun owners. He voted against the 1993 Brady Act, which demanded national background checks. In 2005, then-Rep. Sanders voted for a bill to protect the gun industry from lawsuits related to the criminal use of their products -- legislation that Sen. Clinton had opposed. Sanders, while in the Senate, also voted to allow Amtrak passengers to carry firearms in their luggage.
More recently, the presidential candidate voted to expand background checks for gun buyers, a popular legislative push in 2013 after the Newtown shooting. Sanders also supports an assault weapons ban.
The Republican presidential candidate has an A+ rating from the NRA and has been consistently conservative on gun control.
In April, Bush spoke at an NRA conference in Nashville, where he drew loud applause for slamming the White House on gun control.
"I have a message for the Obama administration," Bush said earlier this year. "Why don't you focus more on keeping weapons out of the hands of Islamic terrorists and less on keeping weapons out of the hands of law abiding Americans?"
As Florida governor, Bush also signed the nation's first "Stand Your Ground" bill into law in 2005.
Republican presidential candidate and South Carolina Sen. Lindsey Graham has been vocal on gun control following the tragic shooting in his state Wednesday.
Speaking with CBS News, Graham put the blame on mental health, rather than gun ownership. He said Thursday of the suspected shooter that he believed "there were some indicators early on that this guy was not quite there."
When asked if there was any possible legislative solution to gun violence, Graham suggested "just being able to track people - put them into systems where they can be deterred or stopped."
Though he added a caveat: "It's very complicated in a nation of 300 million people where you have freedom of movement and freedom of thought. 300 million of us and unfortunately every now and then, something like this happens. And we'll see. But I think usually it's some disturbed person with a gun. That's what, usually, these things are."
Speaking to CNN early Friday morning, the South Carolina senator added to his position on the background check system, saying "the system is failing."
"I'm open minded about modification," Graham said. "How do you fix a system that doesn't work? How do you have a system where 80,000 fail the background check and 9,000 are felons on the run?"
In 2013, the South Carolina senator -- who has said he owns an AR-15 rifle, among other firearms -- voted against a significant expansion in background checks following the 2012 massacre at Sandy Hook elementary school.
"I've always been confident if the Senate debated the Second Amendment, the Second Amendment would win," Graham said two years ago. "Today we saw that President Obama's politically-driven solutions to gun violence could not withstand scrutiny from Congress and the American people."
The White House-backed Senate bill, proposed after the Newtown, Connecticut shooting, sought to ban assault weapons, limit magazine sizes, and expand background checks. With his vote, Graham said that Obama "lost on all three."
Presidential candidate and Texas Sen. Ted Cruz firmly believes in preserving the Second Amendment, and has boasted previously about blocking the 2013 bipartisan amendment that would have expanded background checks for gun owners.
Kentucky Sen. Rand Paul is another strong supporter of the Second Amendment and stood firm in that stance against gun control in the wake of the Charleston shooting.
"What kind of person goes into church and shoots nine people?" Paul said Thursday at the Faith and Freedom summit in Washington, D.C. "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. I think if we understand that, we'll have better expectations of what to expect from government."
The Florida senator has yet to address what police officials are calling a "hate crime" in Charleston, but his views on protecting the Second Amendment are clear from his legislative record.
In 2013, following the shooting in Newtown, Connecticut that left 27 people dead, Rubio opposed legislation that would expand background checks for gun buyers.
"This issue cannot just be about guns," Rubio told CBS News' "Face the Nation" two years ago, just as the Senate was gearing up for a debate on the gun control bill. "It has to be holistically about violence as it impacts the whole country. And I hope that we will take the opportunity here over the next few weeks as we debate this bill to look for ways to raise that issue. And I think they would be very supportive of that."
Retired neurosurgeon-turned-presidential candidate Ben Carson has said he "would never advocate anything to interfere with Second Amendment rights."
Though former Texas Gov. Rick Perry has said he's wary of open carry gun laws, the GOP contender opposes other restrictions on the right to bear arms.
Just days after the shooting in Newtown, Connecticut, Perry said to a tea party gathering that he would support arming teachers in schools.
"One of the things that I hope we don't see from our federal government is this knee-jerk reaction from Washington, D.C., when there is an event that occurs, that they come in and they think they know the answer," he said.
Mike Huckabee's pro-gun stances, even in the wake of shooting tragedies like that at Sandy Hook Elementary School in 2013, have led him to an A+ grade from the NRA.
Former technology executive Carly Fiorina, who is a supporter of the Second Amendment, accused Obama of "pushing a political agenda" in the immediate aftermath of the Charleston shooting.
Louisiana Gov. Bobby Jindal, who is expected to announce his decision on running for the White House next week, echoed Fiorina's remarks on Fox News: "It was completely shameful, within 24 hours of this awful tragedy... we have the president trying to score cheap political points."
"His job as commander-in-chief is to help the country to begin the healing process," Jindal added. "For whatever reason he always tries to divide us. Today was not the moment, this was not the time."