President Joe Biden on Tuesday pointed to his record as a senator getting a ban on military-style rifles through Congress as proof that legislation limiting firearms is possible. But Congress has grown more partisan since Biden’s time on Capitol Hill, and gun control has become one more issue that some Democrats say is too important to let Republicans block.

Senator Richard Blumenthal, a Connecticut Democrat, called on lawmakers to take advantage of a “new era” in the debate over gun ownership and sales, with Democrats now controlling the White House and Senate.

“Inaction by this Congress makes us complicit,” Blumenthal said Tuesday at a Judiciary Committee hearing. “Now is a time for us to honor these victims with action, real action” and “not the fig leafs” offered by Republicans.

Republicans on the panel argued for narrowly tailored changes to existing laws to keep firearms out of the hands of the mentally ill or criminals and bolstering penalties for government agencies that fail to report to the National Instant Criminal Background Check System.

Senator Ted Cruz, a Texas Republican, said Democrats are working to “scape goat” innocent gun owners who are exercising their Second Amendment rights, and he implored lawmakers to “go after murderers” and not law-abiding citizens.

The previously scheduled hearing on gun violence follows Monday’s mass shooting at a Boulder, Colorado, supermarket that left 10 people dead and a shooting spree that left eight people dead at three Atlanta-area massage businesses one week ago.

Read More: Gun Background Check Votes Highlight Growing Party Polarization

The House this month passed two measures on nearly party-line votes designed to improve and bolster background checks. One, H.R. 8, would require background checks for all firearms sales, including at gun shows, and another, H.R. 1446, would prevent gun sales from proceeding if a background check isn’t completed within three days.

Biden on Tuesday said the Senate should act on both of the House bills, and should work on banning assault-style weapons and high capacity magazines

“The United States Senate — I hope some are listening — should immediately pass the two House-passed bills that closed loopholes in the background check system,” Biden said. “This is not — it should not be a partisan issue. This is an American issue.”

Senate Majority Leader Chuck Schumer on Tuesday vowed to bring the House background check legislation to the Senate floor, though he didn’t set a timetable. That could foreshadow a partisan fight over the filibuster, because current Senate rules would require support from at least 10 Republicans to end debate and vote on any gun control bill, and there’s broad opposition within the GOP.

Schumer said the recent shootings add to the need to act.

“I will put these bills on the floor,” he said of the House-passed gun measures. “I’ve said that, and it will happen.”

Still, Democrats aren’t united on the legislation. Senator Joe Manchin, a West Virginia Democrat, told reporters he’s “a law-abiding gun owner” who believes the House legislation goes too far.

“I don’t support what the House passed, not at all,” he said, adding that he remains open to tighter background checks of commercial gun sales.

Senate Minority Leader Mitch McConnell said he opposes the House measures but “I’m certainly open to the discussion.” He said Schumer should bring up legislation and then have a “full, robust discussion.”

Manchin, together with Pennsylvania Republican Pat Toomey, led previous Senate efforts to expand background checks in 2013 following the 2012 massacre at Sandy Hook Elementary School. That bill was blocked by a Republican-led filibuster. Manchin, however, has said he won’t support ending filibusters on legislation, although he has said he might support making it more difficult to employ.

Read More: Gun Background Checks Bill May Test Manchin on Filibuster Rule

Speaking before the hearing, Judiciary Chair Dick Durbin said Democratic leaders are still determining which bill will be the first test on the Senate floor in the possible fight over the filibuster. Democrats also are pressing ahead with other legislation that faces Republican opposition, including voting-rights legislation.

“A majority doesn’t count in the United States Senate,” said Durbin, who also is the No. 2 Democratic leader. “So what I’m saying to those who defend the filibuster is, show me that the Senate can operate with a filibuster and still do things that make us a better nation.”

At the hearing, background-check advocate Robin Brule said it’s time to close a loophole in background checks that resulted in her mother’s death in 2016, when a home invader at her Arizona retirement community shot her and a friend while they were eating breakfast. The gunman purchased the weapon on the Internet without a background check.

“I’m a gun owner, and I believe fully in the Second Amendment,” she added. “But I also know that it’s time for Congress to listen to the 90% of Americans who understand that requiring a background check is common sense. Because no family should have to get that call that I got from police 5 years ago –– the worst call in the world.”

Selwyn Rogers, a trauma surgeon and public health expert at the University of Chicago, said gun violence should be treated as a “public health crisis.” He said mental health is a key component, and that gun suicides are growing more prevalent, and that easy access to guns through unregulated purchases are part of the problem.

Rogers said a breakdown of suicides by House congressional districts shows that in 11 districts across Alaska, Arizona, Colorado, Idaho, Montana, Oklahoma, Oregon and Tennessee, more than 100 people each year use guns to end their lives – roughly double the national average, he said.

But other witnesses said lawmakers at both the state and federal level are going too far with their drive to further regulate gun ownership. Geneva Solomon, a California gun-store owner and top official with the National African American Gun Association, said new laws in her home state are “pricing out” minority and other possible purchasers who want to use their Second Amendment rights to protect themselves.

“Bill after bill demonizes the responsible gun owner,” she said.

(Everytown for Gun Safety, which advocates for universal background checks and gun-control measures, is backed by Michael Bloomberg, founder and majority owner of Bloomberg News parent company Bloomberg LP.)

–With assistance from Jordan Fabian.