Civil rights campaigners in the 1950s and 1960s adopted many tools establishing and extending voting rights protections. The best known of these was a piece of federal legislation: the Voting Rights Act that was signed into law on August 6, 1965. But another tool was the constitutional amendment that banned the noxious poll taxes that southern states used to erect wealth barriers to voting by African Americans, Latinos and poor whites.

The 24th amendment, which was added to the U.S. Constitution in January, 1964, declared that:

Section 1. The right of citizens of the United States to vote in any primary or other election for President or Vice President, for electors for President or Vice President, or for Senator or Representative in Congress, shall not be denied or abridged by the United States or any State by reason of failure to pay any poll tax or other tax. Section 2. The Congress shall have power to enforce this article by appropriate legislation.

Five decades after the great advances of 1964 and 1965, the Voting Rights Act has been assaulted by Republican governor and legislators and the right-wing majority on the U.S. Supreme Court, forcing activists to launch new campaigns to renew its core provisions. Those campaigns are vital, especially the effort to restore the Voting Rights Act with the federal Voting Rights Advancement Act of 2015. But so, too, are proposals to go big in defense of voting rights.

How big? How about an amendment to the Constitution that declares:

Section 1: Every citizen of the United States, who is of legal voting age, shall have the fundamental right to vote in any public election held in the jurisdiction in which the citizen resides. Section 2: Congress shall have the power to enforce and implement this article by appropriate legislation.

That amendment, proposed two years ago and reintroduced this year by Congressman Mark Pocan, D-Wisconsin, and Congressman Keith Ellison, D-Minnesota, has gained traction as frustration with assaults on voting rights has grown among members of the House. The amendment proposal now has 39 co-sponsors, including Michigan Congressman John Conyers Jr., the senior member of the chamber who marched with the Rev. Martin Luther King Jr. in the 1960s and championed the Voting Rights Act at the time of its initial passage.

But constitutional amendments require more than just congressional support. To be enacted, amendment proposals must become central to the national discourse.

That’s why it is important that, on Tuesday, the right-to-vote amendment proposal gained the enthusiastic support of a contender for the Democratic presidential nomination, former Maryland Governor Martin O’Malley. That’s important because O’Malley is in a position to bring the amendment proposal into the mainstream of Democratic Party politics, as a participant in upcoming debates, and in the political discussion that extends from them.

Marking the 50th anniversary of the Voting Rights Act while on the campaign trail in the early primary state of South Carolina, O’Malley called for an amendment to “protect every citizen’s right to vote, once and for all.”

“Passing a constitutional amendment that enshrines that right,” he explained, “will give U.S. courts the clarity they need to strike down Republican efforts to suppress the vote.”

Other candidates for the Democratic nomination have incorporated voting-rights advocacy into their messages. In June, former Secretary of State Hillary Clinton spoke out forcefully in favor of legislation to restore vital provisions of the Voting Rights Act that had been shredded by the Supreme Court’s conservative majority. “We should be clearing the way for more people to vote,” she declared, “not putting up every road-block anyone can imagine.”

Vermont Senator Bernie Sanders, who traces his political activism to civil rights campaigning in the early 1960s, has for been an outspoken critic of voter suppression schemes that make it harder for minorities, students and the elderly to vote. In June, he declared his strong support for the Voting Rights Advancement Act, saying that, “The Supreme Court’s 2013 decision gutting the Voting Rights Act was a shameful step backward. The critical civil rights law which protected voters in places with a history of discrimination is as necessary today as it was in the era of Jim Crow laws. We should do everything possible to guarantee the right to vote, not make it harder for people to cast ballots.”

Sanders has also been supportive of constitutional remedies to Supreme Court rulings that have undermined democracy — including an amendment he has sponsored to overturn the Supreme Court’s Citizens United ruling, which removed historic barriers to corporate spending to influence elections.

The renewal and extension of democracy in America is going to require bold action, including constitutional amendments. O’Malley is recognizing this with his call for a constitutional amendment to guarantee voting rights.

Decrying the harsh reality that “voting in America is becoming harder — not easier — thanks to a concerted effort by Republican activists to suppress the vote,” the former governor is incorporating into his campaign an argument that the way to fight back is with “a constitutional amendment to protect every citizen’s right to vote.”

By delivering that message as a presidential contender, O’Malley further identifies himself as a candidate who is not merely identifying the big problems — which counts for something. He is calling for the big solutions — which counts for even more.