On Wednesday night, the Senate failed to break a GOP filibuster on voting legislation that combines the key provisions of two bills: the Freedom to Vote Act and the John Lewis Voting Rights Advancement Act.
The legislation failed by a vote of 49-51. Senate Majority Leader Chuck Schumer changed his vote to "no" before the vote was given so he can make a proposal to reconsider the vote.
The proposed change to the rules will force lawmakers who want to filibuster the bill to come to the Senate floor and speak in opposition. Once these speeches are completed, the Senate will be able to hold a simple majority for final passage.
But Democrats also do not have the votes to change Senate filibuster rules, with West Virginia Sen. Manchin and Arizona Sen. Kyrsten Sinema is expected to oppose such a move.
In a demonstration in support of voting rights and changing Senate rules, members of the Congressional Black Caucus marched to the Senate, warning that no matter what happens, they will not stop fighting to pass it.
"We want the Senate to act today in a favorable way, but if they do not, we will not give up. I am too young to give up," the rep. Jim Clyburn, the No. 3 Democrat in the House, told CNN.
Senate Minority Leader Mitch McConnell on Wednesday defended Senate rule, saying Republicans would continue their track record of maintaining the legislative filibuster he called the "essence of the Senate" the next time they are in the majority.
"It's pretty safe to say this is the biggest day in Senate history," McConnell said. The Republican from Kentucky, without mentioning them, congratulated Manchin and Sinema for their "courage" and with the thought, "that in the very near future the shoe may be on the other foot."
As a result, pressure to change Senate rules sets the stage for a major showdown among Democrats as the party prepares to put two of its own members in place in an effort that appears doomed to fail.
Democrats, who control only 50 seats in the Senate, are under enormous pressure from liberal activists to intervene against the right to vote, and President Joe Biden has trained his focus on the issue as other elements of his domestic agenda stalled.
"The honest answer to God is that I do not know if we can get this done," Biden said. "I hope we can get this done, but I'm not sure."
Schumer gave a passionate speech on Wednesday, defending the pressure to change Senate rules.
"When we discuss this issue, which is so crucial to the source of our democracy, we will all face the critical question: Should members of this House do what is necessary to pass these bills and move them to the President's desk? It is my hope that against waking up in the hearts of our Republican colleagues before the day is over, "he said, adding that if the Senate can not protect the right to vote," then Senate rules must be reformed. "
"Our proposal for a talking filibuster on these pieces of legislation would be the first step towards transferring voting rights, restoring this body and breaking the gravel that we now face in this important issue," Schumer said.
Manchin warns against partial division
In a speech before the vote Wednesday night, Manchin warned against partisan division, arguing that lawmakers should seek compromise, even if it is challenging to do so.
"Allowing a party to exercise complete control in the Senate with only a simple majority will only fuel the fire of political whiplash and dysfunction that is tearing this nation apart," Manchin said in the Senate. "You do not have to look very far to see how we tear ourselves apart. Every single part of this country is people divided now."
"It's time we did the hard work to create difficult compromises that can stand the test of time," Manchin said.
This story and headline has been updated with further developments on Wednesday.
CNN's Lauren Fox and Jessica Dean contributed to this report..