CNN  — 

President Joe Biden on Tuesday used the latest mass shooting to offer his most vocal push for gun control since taking office, saying the deaths of 10 people at a grocery store in Colorado should jolt Washington and the nation into action.

It was a message past presidents have also wielded to disappointing results. But Biden – who has a lengthy and mixed record on the issue – signaled he was ready to press for legislation even as he balances other priorities in Congress.

In somber remarks from the White House State Dining Room, he said he would do everything in his power to keep Americans safe and pushed a pair of House-passed gun reforms, including a universal background checks measure and an assault weapons ban.

After acknowledging there were still outstanding details to be learned about Monday’s massacre, including the shooter’s motive and weapons, Biden insisted enough was known to make an ardent call for new gun control.

“I don’t need to wait another minute, let alone an hour, to take common sense steps that will save lives in the future,” he said, listing a ban on assault weapons and high-capacity magazines, as well as strengthening the background check system by closing loopholes, as areas he would like to see Congress act.

“This is not – it should not be – a partisan issue. This is an American issue,” he said. “It will save lives, American lives. We have to act.”

Yet the complications in pushing for gun control at a moment when a number of other legislative priorities are looming was immediately apparent. Biden departed the White House directly following his remarks for a visit to Ohio, where he is promoting the $1.9 trillion stimulus measure passed earlier this month. Aides are also preparing an infrastructure package that is expected to be unveiled soon.

Asked during his tour of the oncology department at The Ohio State University whether he believed he had the political capital to move ahead with gun control, Biden crossed his fingers.

“I hope so. I don’t know,” he said. “I haven’t done any counting yet.”

Biden noted on Tuesday that the White House flag was still flying a half-staff to honor the victims of last week’s shooting in Atlanta when the Colorado incident occurred. He ordered it lowered again.

The President had made no mention of gun control in the aftermath of the Atlanta shooting – including during remarks after visiting the city – choosing to focus instead on a recent spate of violent crimes committed against Asian-Americans.

But he faced increasing pressure to voice an opinion on the matter after another mass killing in Colorado.

Earlier Tuesday, Vice President Kamala Harris called the shooting “absolutely tragic,” but ignored a question about the future of gun control during a swearing-in ceremony for William Burns as CIA director.

As the nation’s posture on guns has evolved, Biden has been front-and-center at most every stop along the way for more than three decades, from the triumph of a 10-year ban on assault weapons in 1994 to the disappointment of a failed push for universal background checks in the wake of the Sandy Hook massacre.

But now Biden commands a bully pulpit that he’s never had in the debate over guns in America, facing the challenge of how – or whether – to wield the power of the White House to try and make some type of gun reform legislation a reality.

The shootings in Georgia and Colorado come in the first chapter of his presidency, prompting a discussion inside the West Wing over how much political capital Biden should expend on the matter, which has so often ended in frustration. But the debate comes at a time when the powerful gun lobby is divided and weakened, creating what some allies see as a possible opening for Biden.

“Nothing frustrated President Obama more than his failure to achieve gun reform, but Biden may have the chance to do something Obama just couldn’t do,” a top aide to Obama told CNN, speaking on condition of anonymity to talk candidly about Obama’s limitations on the matter. “Biden is not seen as threatening to some people in a way Obama sadly was.”

It’s an open question the degree to which Biden wants a debate over guns to consume the political oxygen in his first year, with Covid-19 relief only beginning to take hold and a massive infrastructure bill next up on the agenda. Yet with two mass shootings in the last week alone, aides know it may be a choice already made for Biden.

Meeting with advocates