"What has happened right now would not surprise him, it would disappoint him."

And the slain civil rights icon's daughter, Dr. Bernice King, told Reuters the very thing her father fought and died for was once again under threat.

"There are still efforts and individuals who would like to continue to manipulate voting districts and create a concentrated group of a minority power in our nation that is not necessarily representative of the population of a city, or region or of a state. And so, other challenges to the vote, to the free exercise of the vote. So as long as we have that possibility, voting rights is going to be central."

Republican-led states have enacted a wave of new voting restrictions following the 2020 election, which civil rights groups say disproportionately impact poor and minority voters who lean Democratic.

"Hear me plainly, the battle for the soul of America is not over."

In a fiery speech in Atlanta, MLK's birthplace, on Tuesday, President Joe Biden demanded the U.S. Senate enact a voting rights bill the ensure equal access to the ballot box.

"The right to vote, and have that vote counted, is democracy's threshold liberty. Without it, nothing is possible, but with it, anything is possible."

Dr. Bernice King says she believes her father's vision will yet come true.

"I remain hopeful because there is a young generation that I call the accountability generation that is keeping us honest, and so as long as all of those things are working together, and my faith in a God that is within this universe and moving in it through people, I know that ultimately we are going to see some change and transformation. It may not be everything at one time, but we will have victories along the way."