Washington CNN  — 

The first glimpse of how presidential hopefuls might navigate the nation’s racial tension came tragically in the form of a white gunman who sat through a Bible study at a historically black church, then killed nine of the 13 people in the sanctuary.

For President Barack Obama, it’s become a sad, all too familiar ritual, walking to the White House press room to condemn another round of gun violence.

But for many of the candidates seeking to succeed him, it was the first time in their young campaigns they had to confront such a shocking moment. And their varied reactions spoke to the political complexities surrounding race, religion and gun violence. Some, like Florida GOP Sen. Marco Rubio, expressed sadness on Twitter, but avoided speaking directly about the shooting. Others, like former Florida Republican Gov. Jeb Bush, canceled events and expressed condolences for the victims. Democratic frontrunner Hillary Clinton took on the issue directly, calling for more action on gun violence and race. And Vermont Sen. Bernie Sanders called the shooting an “act of terror.”

READ: Clinton, Obama seek gun control in wake of Charleston massacre

Still, it fell to Obama, who has 19 months left in the White House, to harness a sense of national unity. There were personal overtones to Obama’s reaction because he knew the church’s pastor, Rev. Clementa Pinckney, and is well aware of the church’s roots dating back to the days of slavery.

“Mother Emanuel is, in fact, more than a church,” Obama said. “This is a place of worship that was founded by African-Americans seeking liberty. This is a church that was burned to the ground because its worshipers worked to end slavery. When there were laws banning all-black church gatherings, they conducted services in secret.”

But on the campaign trail, careful responses from many candidates reflected the fraught politics of race and violence over the past year as protests have erupted from Ferguson to Baltimore.

The GOP candidates avoided using words like terrorism to describe the massacre, even as progressives framed it that way. According to witnesses, the suspect, Dylann Roof, said he was specifically targeting black people. But many Republican candidates tried to steer clear of the race issue altogether.

South Carolina Sen. Lindsey Graham, who canceled his presidential campaign events to return to Charleston and meet with his constituents, said in an interview with CNN that the shooting should not be viewed as reflective of South Carolina. With so little known about the suspect’s motives, Graham said it was unclear whether there was any tie-in to racial tensions across the U.S.

“I just think he was one of these whacked out kids. I don’t think it’s anything broader than that,” said Graham, whose niece attended an 8th grade English class with suspect. “It’s about a young man who is obviously twisted.”

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“No one at home (in South Carolina) believes this represents us. We don’t want to be judged by him,” Graham said.

Former Pennsylvania Sen. Rick Santorum framed the massacre another assault on religious liberty.

Kentucky Sen. Rand Paul, who has been one of the most outspoken Republicans about the need to broaden the appeal of the party to African-Americans, deplored the “sickness” in America that could lead to such an event. He seemed to liken the incident to a crises of faith before an audience of Christian conservatives.

“What kind of person goes in a church and shoots nine people? There’s a sickness in our country. There’s something terribly wrong but it isn’t going to be fixed by your government,” he said at the Faith & Freedom coalition in Washington. “It’s people straying away, people not understanding where salvation comes from. And I think that if we understand that, we’ll understand have better expectations of what we get from our government.”

Among Republicans, retired neurosurgeon Ben Carson, an African-American, was the only candidate to speak directly about race, noting that someone close to him lost relatives in the shooting.

“In my lifetime I have seen such great progress. Though racial based hate is still very much alive as last night so violently reminded us,” he wrote on his Facebook page. “But I worry about a new hate that is growing in our great nation. I fear our intolerance of one another is the new battle ground of evil.”

The shooting occurred just hours after Clinton left Charleston, where Sanders was also set to hold an event on Sunday. The Vermont senator, who was criticized for holding a loud rally on Thursday next to a prayer circle on Capitol Hill, sent an email to his supporters and asked for donations to the church. He called it a “horrific reminder,” that we are “far from eradicating racism.”

“What transpired in Charleston, South Carolina last night was not just a tragedy, it was an act of terror,” he wrote. “Nine of our fellow Americans were murdered while praying in a historic church because of the color of their skin.”

Speaking at a conference of Latino elected officials in Nevada, Clinton said the “shock and pain of this crime of hate strikes deep.”

“In the days ahead, we will once again ask what led to this terrible tragedy and where we as a nation need to go. In order to make sense of it, we have to be honest,” she said. “We have to face hard truths about race, violence, guns and division.”

At least one hard truth that Obama admitted in his remarks is that movement on gun control is unlikely to happen on his watch as “the politics in this town foreclose a lot of those avenues right now.”

“At some point it’s going to be important for the American people to come to grips with it, and for us to be able to shift how we think about the issue of gun violence collectively,” he said.

On race, a topic he confronted most recently in the wake of the death of a young black man in Baltimore that led to the indictments of several police officers, Obama tied “Mother Emanuel,” to the 16th Street Baptist Church in Birmingham, Alabama, where four black girls died under the rubble of their sanctuary one Sunday morning five decades ago.

“The fact that this took place in a black church obviously also raises questions about a dark part of our history. This is not the first time that black churches have been attacked,” he said. “And we know that hatred across races and faiths pose a particular threat to our democracy and our ideals.”

While part of Obama’s appeal – among blacks and whites – was the expectation that he could help bridge the racial divide, the string of racially charged incidents has put race relations at the forefront of issues important to African-Americans. At the beginning of 2014, 3% of African-Americans thought race relations was the nation’s most pressing issue. That number now stands at 13%, according to a recent Gallup poll. Just 4% of whites hold that view.

Dealing well with race relations is among the perceived strengths of Clinton according to another Gallup poll.

Kelly Adams, a former caucus director for House Democrats and a Clinton 2008 aide, said she has no interest in hearing the 2016 presidential candidates speaking about ‘post-racialism’ in America.

“What I hope comes from this – on both sides of the aisle – is a conversation on how we can make things better and how we can work together regardless of race or political affiliation to heal the state and the nation,” she said.

Obama borrowed from Martin Luther King in his remarks, drawing in part on his 1963 eulogy of the church bombing victims, who King said died nobly and “had something to say to each of us in their death.”

“They say to each of us Dr. King said, black and white alike, that we must substitute courage for caution. They say to us that we must be concerned not merely with (about) who murdered them, but about the system, the way of life, the philosophy which produced the murderers,” Obama said. “Their death says to us that we must work passionately and unrelentingly for the realization of the American Dream.”

In quoting King, Obama suggested the limits of his own rhetoric as a healing balm and the deep-seated nature of a problem stretching back to the country’s founding that will soon fall to a new president to try to address.

CNN’s Eugene Scott contributed to this report.