President Biden accused Republicans of defending voter suppression efforts that amounted to “a Jim Crow era in the 21st Century” in a scathing statement Tuesday after GOP senators blocked debate on a sweeping Democrat-backed election overhaul.

Senate lawmakers voted 50-50 on whether to open debate on the bill known as the “For the People Act,” leaving Democrats short of the 60 votes required to overcome a GOP filibuster. The vote marked a major setback for a piece of legislation that Biden and other prominent Democrats have championed for months in response to the passage of election security overhauls in GOP-led states.

“Today, Democrats in Congress unanimously came together to protect the sacred right to vote. In supporting the For the People Act and defending the rights of voters, they stood united for democracy,” Biden said. “They stood against the ongoing assault of voter suppression that represents a Jim Crow era in the 21st Century.

“Unfortunately, a Democratic stand to protect our democracy met a solid Republican wall of opposition. Senate Republicans opposed even a debate—even considering—legislation to protect the right to vote and our democracy. It was the suppression of a bill to end voter suppression—another attack on voting rights that is sadly not unprecedented,” he added.

Republican lawmakers say the legislation would allow the federal government to infringe on the rights of individual states to dictate their own election rules. The GOP has also argued the bill is meant to unduly benefit Democrats.