Democrats are seizing on this week’s anniversary of the deadly US Capitol riot to renew a push for voting rights legislation to safeguard democracy.

Majority leader Chuck Schumer announced on Monday that the Senate will vote on changing its own rules on or before 17 January, the federal Martin Luther King Jr Day holiday, if Republicans continue to obstruct election reform.

The deadline appears part of a concerted effort to use Thursday’s commemorations, marking a year since a mob of Trump supporters stormed the Capitol, seekingto overturn Joe Biden’s election win, to give fresh impetus to the long-stalled legislation.

In a letter to Senate Democrats, Schumer argued that the events of 6 January 2021 are directly linked to a campaign by Republican state legislatures to impose voter restriction laws.

“Let me be clear,” the New York senator wrote. “6 January was a symptom of a broader illness – an effort to delegitimise our election process, and the Senate must advance systemic democracy reforms to repair our republic or else the events of that day will not be an aberration – they will be the new norm.

“Much like the violent insurrectionists who stormed the US Capitol nearly one year ago, Republican officials in states across the country have seized on the former president’s Big Lie about widespread voter fraud to enact anti-democratic legislation and seize control of typically non-partisan election administration functions.”

Sweeping voting rights reforms have stalled in the evenly split 50-50 Senate, repeatedly blocked by a Republican-led filibuster, leaving Democrats unable to find the 60 votes needed to advance. Schumer went further than before in calling for a filibuster exception for voting rights.

“We must ask ourselves: if the right to vote is the cornerstone of our democracy, then how can we in good conscience allow for a situation in which the Republican party can debate and pass voter suppression laws at the state level with only a simple majority vote, but not allow the United States Senate to do the same? We must adapt. The Senate must evolve, like it has many times before.”

He added: “We hope our Republican colleagues change course and work with us. But if they do not, the Senate will debate and consider changes to Senate rules on or before 17 January, Martin Luther King Jr Day, to protect the foundation of our democracy: free and fair elections.”

Although Schumer’s words were ostensibly aimed at Republicans, there is little prospect of any members of that party shifting their position.

On Monday, Republicans swiftly condemned what they described as a threat. Senator Mike Lee of Utah said: “Senator Schumer’s rash, partisan power grab should be seen for what it is – desperation and a failure to do what Joe Biden and Democrats ran on: unify.

“If this rule change were to pass, the people of Utah and the United States would suffer immeasurably as the Senate devolves into a strictly majoritarian, Lord-of-the-Flies environment. Senator Schumer and his disastrous plan must be stopped.”

But Schumer’s true target, amid blanket media coverage of this week’s anniversary, is likely to be Democratic holdouts Joe Manchin and Kyrsten Sinema, who have resisted abolishing or changing the filibuster.

The senators from West Virginia and Arizona contend that if and when Republicans take control of the chamber, they could use the lower voting threshold to advance bills Democrats oppose.

Schumer’s announcement is likely to set up 6 January vigils and Martin Luther King Jr Day events as rallying points for voting rights activists who have criticised Biden and the party in Congress for failing to prioritise the issue.

But the president has become less cautious and more direct.

Last month, he told ABC News: “If the only thing standing between getting voting rights legislation passed and not getting passed is the filibuster, I support making the exception of voting rights for the filibuster.”

Schumer’s announcement was welcomed by Martin Luther King III, son of the civil rights activist and chairman of the Drum Major Institute.

“There is no better way to honor my father’s legacy than protecting the right to vote for all Americans,” he said.

“The King holiday is historically a day of service, and we hope the United States Senate will serve our democracy by passing the Freedom to Vote Act and the John Lewis Voting Rights Advancement Act.

“We applaud Senator Schumer for his commitment to expanding voting rights, but we won’t halt our plans for action until legislation has been signed.”

Also on Monday, the US Conference of Mayors sent a letter signed by 146 bipartisan mayors to Schumer and the minority leader, Mitch McConnell, urging them to act this month. It noted that in the past few months alone, 19 states passed 34 laws that made it harder to vote.

The mayors wrote: “American democracy is stronger when all eligible voters participate in elections. Yet voting rights are under historic attack and our very democracy is threatened.

“These bills would stop this voter suppression. They would create national standards for voting access in federal elections that would neutralize many of the restrictive voting laws passed in the states.”