Democrats’ months-long drive for muscular new federal voting rights legislation hit a new roadblock Wednesday, with options for progress dwindling as Senate Republicans remained united in blocking debate on the issue.

Outwardly, key lawmakers and advocates have continued to elevate the political stakes, calling federal legislation essential to protecting American democracy from the efforts of Republican state legislatures and election officials to restrict voting access following former president Donald Trump’s false claims of rampant fraud in the 2020 presidential election.

“If there’s anything worthy of the Senate’s attention, if there’s any issue that merits debate on this floor, it’s protecting our democracy from the forces that are trying to unravel it from the inside out,” Senate Majority Leader Charles E. Schumer (D-N.Y.) said Wednesday.

But the realities of the Senate — with a razor-thin Democratic majority and a united Republican minority empowered by the long-standing filibuster rule requiring a 60-vote supermajority to advance most legislation — continue to make progress difficult and wholly dependent on the willingness of key Democratic senators to change their views on modifying the Senate’s rules.

Wednesday’s vote, which would have paved the way for a floor debate on voting rights, failed 51 to 49, with 60 votes needed to advance the legislation. For procedural reasons, Schumer joined all 50 Republicans in voting no.

The vote was meant, in part, to demonstrate the depth of the Republican opposition to one of the holdouts over changing the filibuster rule, Sen. Joe Manchin III (D-W.Va.), who played a leading role in crafting a narrower alternative to the sprawling bill that Senate Republicans blocked in June.

The new bill, called the Freedom to Vote Act, keeps some provisions of the earlier bill, including national standards for early voting and vote-by-mail, new disclosure requirements for “dark money” groups and the establishment of Election Day as a federal holiday. But it also discards or scales back controversial provisions such as a reworking of the Federal Election Commission, a major new public financing system for congressional elections and a mandate for nonpartisan redistricting commissions. It also omits major revisions to the ethics regime for federal officeholders.

The procedural vote Wednesday came after Manchin spent the past month wooing Republican colleagues — including Senate Minority Leader Mitch McConnell (R-Ky.) — to support it. Yet no Senate Republican emerged before Wednesday to support the bill — let alone the 10 needed to join Democrats to start debate on it.

McConnell on Wednesday said the GOP remains steadfastly against any federal legislation and accused Democrats of trying to “truss up the same takeover with new trappings.”

“The same rotten core is all still there,” he said, denouncing provisions of the bill that would impose new federal mandates on state election practices, an argument that has won a broad following among even the most moderate GOP senators.

Now Manchin is facing new pressure to sketch out a path around the continued Republican opposition — the culmination of a months-long process designed by Democratic leaders to demonstrate that there is no bipartisanship to be had on the voting rights issue.

“Joe Manchin has been given all summer to both draft and negotiate this bill,” said Meagan Hatcher-Mays, director of democracy for the Indivisible network of liberal activists. “He is the one who holds the key as to whether or not this bill will actually pass. So the question for Joe Manchin [on Wednesday] is, are you going to show more loyalty to our democracy and our country? Or are you going to show more loyalty to an arcane Senate rule that is arbitrarily blocking your own legislation from being passed?”

Sen. Raphael G. Warnock (D-Ga.), who faces reelection next year in a state where GOP legislators have tightened voting laws, put it more diplomatically on Tuesday.

“It’s urgent. The clock is ticking. We need to get this done,” Warnock said.

But it remains unclear how — or if — Manchin will respond. He did not comment or release any statement Wednesday on further steps he would support to advance the legislation, and while he has at times signaled openness to changing the Senate rules to encourage debate, he has firmly and repeatedly opposed the elimination of the filibuster.

Meanwhile, Sen. Kyrsten Sinema (D-Ariz.), who has long supported new voting rights legislation but opposed changes to the filibuster, has given no indication that she has changed her views. Several other Democratic senators have been less outspoken but still remain wary of eliminating the filibuster entirely while being open to modifications.

Schumer has repeatedly vowed that “failure is not an option” on voting legislation, and he has said Democrats would gather and decide collectively as a caucus on how to proceed with changing Senate rules. But the latest vote comes at an inopportune time for any such discussion.

While many Democratic senators said this week that they consider voting rights to be the most important issue at stake for Congress — or at least one of equivalent importance to President Biden’s Build Back Better economic agenda, which is now crawling across Capitol Hill — the push to deliver on trillions of dollars of domestic policy priorities has clearly taken precedence.

This week, for instance, at least 19 lawmakers traveled to the White House to meet with Biden about clinching a deal to pass the two economic bills — funding infrastructure and the remainder of his domestic agenda. On voting rights, the White House released a statement Tuesday confirming two calls Biden made to senators about voting rights — both of whom already support the legislation — and saying that the administration is pushing for progress “through legislation, executive actions, outreach, the bully pulpit, and all other means available.”

The fact that the same two senators — Manchin and Sinema — are at the center of both the Build Back Better and voting rights struggles has only added to the complications.

“The reality of this world is that Build Back Better will consume massive amounts of oxygen as long as it’s left undone,” said Adam Jentleson, a former senior Senate Democratic aide and an advocate for elimination of the filibuster. “But having this vote, having it fail and showing that there are not 10 Republicans who are willing to come forward and save our democracy is an important and necessary part of the process.”

Sen. Tim Kaine (D-Va.) acknowledged that the throes of the Build Back Better negotiations are unlikely to be a productive moment for an internal reckoning over the filibuster. But, he said, Democrats are “not going to let it drop.”

“It doesn’t have to happen like right now, like tomorrow afternoon,” he said Tuesday. “But what if we reach an agreement on [Build Back Better] this week? . . . We can also be having a discussion about, hmm, we’re not going to abolish the filibuster, but are there things to restore the Senate as a place that will protect voting rights that we can do?”

Schumer, speaking on the Senate floor after the vote, made no direct mention of Manchin or the filibuster but instead vowed to fight on — comparing the effort to Republican attempts to secure civil rights for people newly freed from slavery after the Civil War.

“Members of this body now face a choice,” he said. “They can follow in the footsteps of our patriotic predecessors in this chamber. Or they can sit by as the fabric of our democracy unravels before our very eyes.”

Across the aisle, there appears to be little concern that Manchin or Sinema is at risk of changing their minds to advance voting rights legislation.

McConnell and other Republicans have shown some concern that the moderate duo might move under some circumstances to undermine the filibuster, which has driven decisions by some Republicans to embrace a bipartisan infrastructure deal this summer and to retreat from a high-stakes confrontation on the federal debt ceiling earlier this month. But they say they remain confident that neither Democrat will undermine the filibuster to pass voting rights legislation.

“We take him at his word — the filibuster’s safe,” said Sen. John Cornyn (R-Tex.) of Manchin.

Whether or not Manchin or Sinema can be persuaded to change their minds on the Senate rules, Democrats are under immense pressure to keep hope alive — because of political pressure from their base, the potential impact of state voting law changes on the 2022 elections and beyond and the continued stream of false claims of fraud from Trump and his allies.

Yet Democrats are already facing diminishing returns on any legislation that ultimately might be passed. States, for instance, have already launched their decennial redistricting processes, making it increasingly difficult — if not impossible — to impose new federal line-drawing guidelines ahead of next year’s election. And with every day that passes, it becomes more difficult to impose other national voting mandates as state and local election officials gear up for the coming primary and general elections.

But multiple lawmakers and advocates said they had no choice but to fight despite the long odds of success. Sen. Chris Murphy (D-Conn.) called it a “job requirement” for Democrats.

“Whether or not we have a viable pathway to getting this or any bill passed, if you aren’t waking up every day and working on improving our democracy, you are going to rue the day when it falls,” he said. “Maybe we get a bill passed. Maybe we don’t. But by working on it every week, we’re translating a value to the American public about how much we think democracy is under threat.”