WASHINGTON -- It was as if the two major political parties' presidential hopefuls were in separate universes Thursday, as the Democratic candidates consistently highlighted the 50th anniversary of the Voting Rights Act while the Republicans didn't even acknowledge its existence during their first primary debate.

The three leading contenders for the 2016 Democratic nomination -- former Secretary of State Hillary Clinton, Sen. Bernie Sanders (I-Vt.) and former Maryland Gov. Martin O'Malley -- have offered sometimes distinct and sometimes overlapping proposals for how to restore the landmark legislation, which was gutted by the Supreme Court in 2013. All have spoken in favor of Congress restoring the weakened VRA.

O'Malley has called for a constitutional amendment that would guarantee the right to vote. The concept has been proposed in Congress by Reps. Mark Pocan (D-Wis.) and Keith Ellison (D-Minn.), who have introduced legislation for an amendment stating, 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.

Clinton has also backed a variety of proposals to expand ballot access. On Thursday, her campaign commemorated the VRA's anniversary with a Tumblr blog where supporters could recount the first time they voted . In June, Clinton advocated for automatic, universal registration , which has become an increasingly popular idea for Democrats since Oregon passed its first-in-the nation law earlier this year.

Sanders also made voting rights a centerpiece of his campaign Thursday. In a blog for The Huffington Post , he wrote about his legislation to establish universal voter registration and his bill that would make Election Day a national holiday. He's also called for the repeal of the Supreme Court's 2010 Citizens United decision so as to restore restrictions on spending by super PACs -- framing campaign finance and voting rights issues as inextricably linked.

In contrast, voting rights didn't get a single mention during the 90 minute Republican presidential debate Thursday evening. Progressive groups had called on Fox News , which hosted the debate, to ask some sort of question about voting rights given the anniversary of the VRA, which Congress passed with bipartisan support in 1965 and reauthorized on a bipartisan basis multiple times after.

While the Republican candidates were not asked about voting rights -- and didn't choose to bring up the topic -- the Republican National Committee released a statement ostensibly representing the party's views. The statement celebrated the very sorts of measures to expand access, like early and weekend voting, that the GOP candidates on stage have worked to cut back.

New Jersey Gov. Chris Christie vetoed a bill to enact early voting in 2013 . Wisconsin Gov. Scott Walker and Ohio Gov. John Kasich both cut back early and weekend voting in 2014. And former Texas Gov. Rick Perry signed a voter ID law in 2011 that, a federal appeals court ruled Wednesday, violated the VRA .

Of the candidates who are senators, Rand Paul (Ky.), Ted Cruz (Texas) and Marco Rubio (Fla.) have not called for Congress to restore the VRA. Indeed, Cruz celebrated the Supreme Court's decision to invalidate key provisions of the legislation, since unelected federal bureaucrats would no longer be able to prevent states from implementing their own voting laws. (The law the court blocked had mandated that certain jurisdictions with a history of discrimination clear any election changes with the federal government or in federal court.)

Legislation to revitalize the VRA has not gained traction in Congress. Republicans generally say that the wave of voting restrictions passed since they took control of a swath of state legislatures in 2010 is needed to restore faith in elections and combat voter fraud. Democrats say such laws disproportionately impact seniors, students, racial minorities and low-income voters or those with disabilities.

Two Democratic National Committee staffers denounced Republicans' lack of response to the VRA on a press call Friday. Addressing the needs of communities of color is "not even on their radar," said Michael Tyler, the DNC's director of African American media.

Republicans chose Cleveland to appeal to people who have been ignored over the past few decades, as part of a minority outreach campaign called "Committed To Community," Tyler said, adding that the GOP failed miserably in that endeavor.

"If the Republican party wants to demonstrate that they're, hashtag, 'committed to community,' they should demonstrate that through policies that uplift communities of color," he said. "A hashtag is not gon cut it."

If Republicans want to show how dedicated they are to fixing Americas issues they should fight to expand ballot access, quality and affordable healthcare, family leave and overtime pay and raise the minimum wage, Tyler said.

"As long as they continue clinging to their outrageous positions, then their outreach to African-Americans, their outreach to women, their outreach to young people is nothing more than window dressing that wont help solve our nations greatest challenges," he said.