“No matter what happens tomorrow, we must keep the pressure on and say no more empty words. Don’t tell us what you believe in, show us with your votes. History will be watching what happens tomorrow,” Martin Luther King III, son of Martin Luther King Jr. said in a speech in Washington, DC. “Black and brown Americans will be watching what happens tomorrow. In 50 years, students will read about what happens tomorrow and know whether our leaders had the integrity to do the right thing.”

His comments come on the federal holiday honoring the late civil rights leader and a day before the Senate is expected to take up voting rights legislation that faces uncertainty amid opposition among Democrats. The King family and activist groups have been urging President Joe Biden and Congress to act on voting rights legislation that has stalled in the Senate.

On Monday morning, the King family gathered with other activist groups and marched across the Frederick Douglass Memorial Bridge. Their message to Biden and Congress: “You delivered for bridges, now deliver for voting rights.” They marked what would have been King Jr.’s 93rd birthday in Phoenix on Saturday, where they pushed for the President and Congress to pass the voting rights legislation.

House Speaker Nancy Pelosi, Congressional Black Caucus Chairwoman Rep. Joyce Beatty, Alabama Rep. Terri Sewell, DC Mayor Muriel Bowser and activist groups also joined the King family at the news conference on Monday, calling for the Senate to act.

“If you really truly want to honor Dr. King, don’t dishonor him by using a congressional custom as an excuse for protecting our democracy,” Pelosi said, in reference to changing the Senate filibuster rules necessary to pass the legislation.

‘Whose side are you on?’

“The attack on our democracy is real, from the January 6th insurrection to the onslaught of Republican’s anti-voting laws in a number of states,” Biden said in pre-recorded remarks. “It’s no longer just about who gets to vote. It’s about who gets to count the vote and whether your vote counts at all. It’s about two insidious things: voter suppression and election subversion.”

The President continued, “We’re in another moment right now where the mirror is being held up to America, being held up again. The question being asked again: Where do we stand? Whose side are we on?”

Vice President Kamala Harris also called on the Senate to pass voting rights legislation, saying during the Martin Luther King Jr. Beloved Community Commemorative Service at Ebenezer Baptist Church to truly honor King Jr.’s legacy, “We must continue to fight for the freedom to vote, for freedom for all.”

“Today, our freedom to vote is under assault,” Harris said in virtual remarks on Monday. “It is time for the United States Senate to do its job. … The Senate must pass this bill, now.”

Pressure on two Democrats

Democrats have been searching for a way to pass voting rights legislation amid the pressure and pushback from members of their own party.

“Senator Sinema and Senator Manchin want a supermajority. Well, a supermajority of citizens support this legislation,” Arndrea Waters King, wife of Martin Luther King III, said Monday, adding that if both senators maintain their positions they will “extend White supremacy’s chokehold on our democracy.”

Martin Luther King III also criticized both senators and said, “History will not remember them kindly.”

CNN reached out to Sinema’s and Manchin’s offices for comment.

This story has been updated.