The US House of Representatives has passed legislation that would bolster federal resources to prevent domestic terrorism in response to the racist mass shooting in Buffalo, New York – but the bill faces the increasingly familiar burden of an uphill climb to pass the Senate.

The 222-203, nearly party-line House vote was an answer to the growing pressure Congress faces to address gun violence and white supremacist attacks – a crisis that escalated following two mass shootings over the weekend.

Adam Kinzinger of Illinois, a member of the congressional committee investigating the insurrection at the US Capitol by extremist supporters of Donald Trump on January 6, 2021, was the lone Republican to vote in favor of the measure.

But the legislative effort by Democrats is not new. The House passed a similar measure in 2020 only to have it languish in the Senate.

And since lawmakers lack the support in the Senate to move forward with any sort of gun control legislation they see as necessary to stop mass shootings, Democrats are instead putting their efforts into a broader federal focus on domestic terrorism.

“We in Congress can’t stop the likes of [Fox News host] Tucker Carlson from spewing hateful, dangerous replacement theory ideology across the airwaves. Congress hasn’t been able to ban the sale of assault weapons. The Domestic Terrorism Prevention Act is what Congress can do this week to try to prevent future Buffalo shootings,” the Illinois Democrat Brad Schneider, who first introduced the measure in 2017, said on the House floor late on Wednesday night.

“Replacement” theory is a set of racist and antisemitic lies and socio-political arguments that has cropped up around the world in the past decade.

In the US it is expressed as the false idea that a cabal of Jews and Democrats is “replacing” the shrinking white American majority race with Black, Hispanic and other people of color by encouraging immigration and interracial marriage – with the goal of threatening the ruling elite and eventually engineering the extinction of the white race.

It is being investigated as a key motivating factor in Saturday’s supermarket shooting that killed 10 people and wounded three others in Buffalo, New York, 11 of them Black.

Police say an 18-year-old white man drove three hours to carry out a racist, live-streamed shooting rampage in a crowded supermarket. He appeared to have carefully planned the attack and written white supremacist screeds online, also following influences from other mass shootings and self-declaring as a racist anti-migration far-right believer known as an “eco-fascist”.

Supporters of the House bill say it will fill the gaps in intelligence-sharing among the justice department, Department of Homeland Security and the FBI so that officials can better track and respond to the growing threat of white extremist terrorism.

Under current law, the three federal agencies already work to investigate, prevent and prosecute acts of domestic terrorism.

But the bill would require each agency to open offices specifically dedicated to those tasks and create an interagency taskforce to combat the infiltration of white supremacy in the military.

Senate Democrats are pledging to bring up the bill for a vote next week. But its prospects are uncertain, with Republicans opposed to bolstering the power of the justice department in domestic surveillance.

Under the bill, agencies would be required to produce a joint report every six months that assesses and quantifies domestic terrorism threats nationally, including threats posed by white supremacists and neo-Nazi groups.

For decades, terrorism has been consistently tied with attacks from foreign actors, but as homegrown terrorism, often perpetrated by white men, has flourished over the past two decades, Democratic lawmakers have sought to clarify it in federal statute.

“We’ve seen it before in American history. The only thing missing between these organizations and the past are the white robes … it’s time for us to take a stand,” the Illinois Democratic senator Dick Durbin said, nodding to the Ku Klux Klan.

Also on Wednesday, New York’s Democratic governor, Kathy Hochul, unveiled what she called a “comprehensive plan to combat domestic terrorism and prevent gun violence” for the state.