It’s not an exaggeration to say that the U.S. Senate’s filibuster rules threaten not only President Biden’s ambitious domestic agenda but also democracy itself.

With the upper chamber split 50-50, the requirement means that most legislation effectively needs 60 votes to pass. And that means Republicans can block the Democrats from raising the minimum wage, rebuilding our infrastructure and reforming immigration.

More important, the GOP can keep Congress from stopping Republicans’ aggressive efforts in state legislatures across the country to make it harder to vote. The barely disguised purpose of these legislative efforts is to disenfranchise African Americans and other Democratic constituencies. It risks enthroning minority rule and a Trumpist agenda in Congress, beginning with the 2022 midterms and for years to come.

Think that’s alarmist? Consider that the previous president, with broad support from his party, openly tried to overturn an election and still claims without evidence that Biden won only through fraud.

Given such stakes, it’s gratifying that there’s a growing movement within the Senate to weaken the filibuster and eliminate it in some cases — such as to protect voting rights and perhaps make the District a state.

There aren’t enough votes in the Senate yet to kill the filibuster altogether and move to simple majority rule. That’s because at least two Democratic senators, Joe Manchin III (W.Va.) and Kyrsten Sinema (Ariz.), oppose such a far-reaching change. (If they both came around, the Democrats could make the switch with just 50 Senate seats because Vice President Harris would cast the tiebreaker.)

But many Democrats support some kind of change, and more are sure to do so if Senate Republicans use the filibuster to paralyze the chamber, as they did when Barack Obama was president.

The four senators from our region, all Democrats, support the reform efforts, albeit to varying degrees and with an emphasis on moving cautiously. Their views offer a snapshot of the range of Senate Democrats’ positions on this pivotal issue.

Under existing rules, the GOP can effectively block most bills by threatening to mount a filibuster, a mechanism designed to protect minority rights. It used to require opponents to speak endlessly on the floor, but now it’s enough merely to announce one’s intention to do so. A 60-vote majority is then required to move forward.

In our area, Sen. Chris Van Hollen of Maryland is the strongest voice for change. He wants to scrap the filibuster altogether, saying it “just compounds the anti-democratic nature of the U.S. Senate.”

That’s anti-democratic with a small “d.” He referred to the fact that the Senate effectively represents the biggest gerrymander in U.S. politics, in which Wyoming has just as many senators as California even though the latter’s population is 70 times larger.

“I’m very worried that the supermajority rule of the Senate is preventing our country from doing important work right now,” Van Hollen said in an interview.

He would still provide some protection to the minority by guaranteeing them “ample time” to air their positions in debate.

I asked Van Hollen about the risk that the GOP, whenever it regains the majority, would use the change against the Democrats.

“There’s no doubt that there are risks,” he said. “I just think the greater risk to our country right now is our inability to do big important things.”

His fellow Marylander, Sen. Ben Cardin, would be willing to eliminate the filibuster altogether but thinks it’s wiser at present to support lesser steps. He wants to change rules so bills move more quickly to the Senate floor for debate, and guarantee the minority a chance to propose relevant amendments. He would significantly weaken the ability of individual senators to kill bills by placing a “hold” on them.

Even if the 60-vote requirement for final passage were retained, Cardin said, the minority would be more willing to cooperate if there was more debate and a greater ability to make amendments.

“I would be prepared to eliminate the filibuster, but I don’t think you have the votes in the Senate to do it,” Cardin said in an interview. “I’m trying to find a bipartisan buy-in to reforming the Senate. I think that’s far healthier.”

He said senators of both parties have been actively discussing such changes.

“That’s been growing in interest in the last six to eight months,” Cardin said. “The [current] system is broken.”

The two Virginia senators, Tim Kaine and Mark R. Warner, are more cautious than their Maryland colleagues but are open to change.

Kaine wants to go back to requiring opponents of a bill to actually speak continuously on the floor of the Senate in a filibuster. Manchin signaled in a March 7 interview that he could support that reform.

“I was thrilled to hear Joe Manchin say that,” Kaine told CBS the following day. “If you want to stand and stop the majority from passing something, you have to stand on your feet and do it to show the American public it’s that important.”

As for other reforms, Kaine said in an emailed statement that he first wanted to test the GOP’s appetite for compromise: “I’m interested in getting results for the American people, and I hope we will find common ground to advance key priorities. If Republicans try to use arcane rules to block us from getting results for the American people, then we’ll have a conversation at that time.”

Warner, who has supported keeping the filibuster in the past, signaled that he was willing to make an exception and allow a simple majority for passage of bills that protect voting rights. Similar exceptions have already been made for Supreme Court nominations and bills that directly affect the budget, such as the recently passed $1.9 trillion coronavirus relief plan.

“I am still hopeful that the Senate can work together in a bipartisan way to address the enormous challenges facing the country,” Warner said in an emailed statement. “But when it comes to fundamental issues like protecting Americans from draconian efforts attacking their constitutional right to vote, it would be a mistake to take any option off the table.”

That’s a welcome sign for Rep. John Sarbanes (D-Md.), lead sponsor of the “For the People Act,” or H.R. 1, a sweeping measure aimed in large part at blocking GOP efforts to suppress voting. Among other things, it establishes no-excuse absentee voting and guarantees 15 days of early voting nationwide. The House passed it March 3, but it will surely die in the Senate without filibuster reform.

“It’s going to require [Senate] Democrats to reevaluate the rules and look at how they can be adjusted in order to allow critical legislation such as H.R. 1 to pass with a simple majority,” Sarbanes said.

If that’s what it takes to protect representative democracy at a time when it’s under attack, then so be it.