WASHINGTON — Almost six months after lawmakers unveiled bipartisan legislation aimed at amending the gutted Voting Rights Act, the bill is languishing in Congress, leaving voters vulnerable to discrimination, critics say.

In the summer of 2013, the Supreme Court in Shelby County v. Holder struck down Section 4 of the Voting Rights Act, which required states with a history of voting discrimination to clear any changes to their voting laws with the Department of Justice. The court, however, also said in the majority ruling that Congress was free to come up with a new formula for which states would face additional scrutiny, taking into account their more recent brushes with voting rights infringements.

To that end, in January, Rep. Jim Sensenbrenner, R-Wis., Rep. John Conyers, D-Mich., and Sen. Patrick Leahy, D-Vt., sponsored a bill that created a new coverage formula for which states would have to submit future voting law changes to the federal government for preapproval. Under the new criteria, if a state has more than five violations of federal law pertaining to voting rights in the past 15 years, it would have to obtain clearance from the Justice Department to implement new ordinances. Those states would include Georgia, Louisiana, Mississippi and Texas, according to a report in The Nation.

But as the November elections rapidly approach, the House Judiciary Committee, chaired by Republican Rep. Bob Goodlatte of Virginia, has not moved to schedule a hearing or a markup on the legislation, to the dismay of voting rights groups that have been pushing for Section 4 to be reinstated. Leahy, meanwhile, has not been able to find Republican co-sponsors for the bill in the Senate.

“The process is what’s stalling,” said Nicole Austin-Hillery, counsel and director of the Washington, D.C., office of the Brennan Center for Justice, a voter advocacy group. “There have been lots of conversations with members of both parties, and with the leadership within the Republican Party, but we've got to get a hearing.”

Austin-Hillery said Goodlatte, as well as members of the House leadership including Majority Leader Eric Cantor, R-Va., have been receptive to the idea of considering the legislation, but have asked for additional information regarding which states are currently being accused of discriminatory voting practices and if those states would be covered under the new proposal.

“Those are valid questions, but I think the position of the voting rights community is that those are the types of question that should be asked in a hearing,” she said. “That is the purpose of a hearing.”

Jotaka Eaddy, senior director of voting rights at the NAACP, also said voting rights organizations were more than happy to furnish additional information, but moving forward with the legislative process was integral in the next few weeks. The hope of activists is to get a bill to the president’s desk in advance of the 2014 midterm elections, when millions of Americans will go to the polls.

“We are making very clear the need for this legislation to move forward in the congressional process so that we can have the conversation,” Eaddy said. “The risk is just too great for voters.”

The NAACP provided an extensive memo to the House Judiciary Committee outlining various instances of discriminatory voting practices signed into law in the past year that have an outsize impact on vulnerable populations. The North Carolina Legislature, for instance, almost immediately passed an omnibus voting bill that instituted an ID requirement, cut down on early voting days and imposed further voter registration restrictions. A similar bill instituting a strict voter ID requirement also passed in Texas. In Georgia, lawmakers have put forward proposals to roll back the number of polling places, hampering access, critics said.

For his part, Goodlatte remains tight-lipped on his thinking around the amendment. No hearing has been scheduled.

“I fully support protecting the voting rights of all Americans,” he said in a prepared email response. “As Congress determines whether additional steps are needed to protect those rights, I will carefully consider legislative proposals addressing the issue.”

A senior House Judiciary Committee aide said negotiations were ongoing but stalled, partly because of the political considerations in play within the Republican caucus — including the fact that much of the new voting legislation seems to deter Democratic-leaning constituencies from going to the polls. The aide, requesting anonymity so as not to upset the talks, said the last time the Voting Rights Act was reauthorized, in 2005, it had the support of President George W. Bush.

“In this particular instance, you don’t have the titular head of the Republican Party pushing in any particular directions, and there are lots of little factions,” the aide said. “With there not being any impetus either way, you end up in limbo, which is where we are.”

Advocacy efforts continue, activists said, with lobbyists descending on Capitol Hill to ask every GOP member of the House to put his or her weight behind scheduling a hearing.

“This is the most important thing in making our democracy work — to keep our elections accessible, fair and free,” said Elisabeth Macnamara, president of the League of Women Voters. “The Voting Rights Act has been the jewel in the crown of accomplishing that for the last half a century, and we need to keep the commitment going to make sure every eligible voter has the opportunity to cast their ballot.”