US President Barack Obama speaks on economy in the South Court Auditorium of the Eisenhower Executive Office Building, next to the White House, in Washington, on September 16, 2013 to mark the five-year anniversary of the financial crisis. The White House marked the fifth anniversary of the financial crisis with a new bid to claim credit for "bold" emergency economic rescue measures it said worked better than anyone expected. AFP Photo/Jewel Samad (Photo credit should read JEWEL SAMAD/AFP/Getty Images) File photo of President Barack Obama. (Photo by JEWEL SAMAD/AFP/Getty Images)

WASHINGTON (CBSDC/AP) — President Barack Obama on Monday wearily lamented “yet another mass shooting,” this time in the nation’s capital where the debate that raged earlier this year over tightening firearms laws has stalled amid opposition from gun-rights advocates.

The shooting at the Washington Navy Yard came a week after voters recalled two Colorado legislators who supported tougher gun measures, illustrating the strong political headwinds faced by lawmakers seeking to respond to the violence.

Obama, for one, has been powerless to get legislation passed despite a string of mass shootings during his presidency.

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In the wake of the shooting at the Navy Yard, Obama spokesman Jay Carney said the president is implementing executive actions and reiterated his commitment to strengthening gun laws, including expanding background checks to sales online and at gun shows.

“The president supports, as do an overwhelming majority of Americans, common-sense measures to reduce gun violence,” Carney said.

Even as it was unfolding, the Washington shooting was reigniting talk about guns. Sen. Dianne Feinstein, a leading advocate of gun control legislation, mourned “the litany of massacres” the country has suffered in the form of mass shootings.

“When will enough be enough?” Feinstein asked. “Congress must stop shirking its responsibility and resume a thoughtful debate on gun violence in this country. We must do more to stop this endless loss of life.”

But it was far from certain whether the shooting would actually influence the larger debate over gun control vs. gun rights, given that the already difficult politics of the issue have gotten only tougher since December’s shooting at Connecticut’s Sandy Hook Elementary School. That shooting, which killed 20 first-graders and six staffers, spurred Obama to propose stricter firearms laws to prevent future deaths.

Gun owners, aided by their advocates at the National Rifle Association, have successfully fought Obama’s legislation, even though polls show broad support for tougher gun laws.

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Obama and gun control advocates have vowed to continue fighting since the Senate rejected expanded background checks in April, but they can’t point to a single new Senate supporter. Their case wasn’t helped by last week’s NRA-backed recall of two Colorado Democratic senators who supported expanded background checks and limits on ammunition magazines.

Matt Bennett, senior vice president at Democratic-leaning Third Way, says the Colorado senators’ mistake was banning high-capacity magazines — even though Third Way has supported such a ban.

“We do as good public policy, but we don’t support Congress trying to do it at this point because it’s bad politics,” Bennett said. “Voters don’t like it.”

New York City Mayor Michael Bloomberg, an advocate for stricter gun laws with his group Mayor’s Against Illegal Guns, contributed around $350,000 to support the Colorado Democrats — Senate President John Morse and Sen. Angela Giron. The NRA spent roughly the same amount opposing them.

Mark Glaze, executive director of Mayors Against Illegal Guns, said the group will continue to “give legislators who take risks to protect public safety the resources to defend themselves.” He said it may take some time, but predicted eventually they will have support in the Senate for tighter laws.

“It’s a question of how long some senators think they can politically sustain doing nothing while 33 more Americans die every day and the mass shootings continue,” Glaze said.

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Obama didn’t mention gun control as he addressed the Navy Yard shooting from the White House, promising to pursue “whoever carried out this cowardly act.”

“We are confronting yet another mass shooting, and today it happened on a military installation in our nation’s capital,” Obama said. “It’s a shooting that targeted our military and civilian personnel. These are men and women who were going to work, doing their job protecting all of us. They’re patriots, and they know the dangers of serving abroad, but today they faced the unimaginable violence that they wouldn’t have expected here at home.”

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