(CNN) Alabama's only Democratic member of Congress is requesting the Justice Department investigate the state's decision to close 31 driver's license offices, arguing the move could curtail the voting rights of residents in poor, rural, mostly-African American communities.

Alabama began requiring that voters present valid photo identification to cast a ballot in 2014.

Rep. Terri Sewell, who is also the only African-American in the state's congressional delegation, sent a letter to U.S. Attorney General Loretta Lynch on Monday calling for a "full and thorough investigation" into the matter.

"This decision will leave eight out of the 10 counties with the highest percentage of non-white registered voters without a Department of Motor Vehicles to issue an Alabama driver's license," Sewell wrote in the one-page letter. "This fact combined with Alabama's voter ID law means that the DMV closure decision will disproportionately affect African-American voters in violation of their constitutionally protected right to vote."

Sewell also requested that Justice officials, through the department's Office of Community Engagement, join her at town hall meetings in the affected communities to talk about the impact of the closures.

Her request for an investigation comes after Democratic front-runner Hillary Clinton also denounced the move, which the state agency blamed on budgetary issues.

"I strongly oppose Alabama's decision to close driver's license offices across the state, especially in counties that have a significant majority of African-Americans," Clinton said in a statement, adding that several of the affected counties are more than two-thirds black.

"Just a few years ago, Alabama passed a law requiring citizens to have a photo ID to vote. Now they're shutting down places where people get those photo IDs. This is only going to make it harder for people to vote. It's a blast from the Jim Crow past," Clinton said.

Arguing the government should be making it easier for citizens to vote, not harder, Clinton said as president she would push for automatic voter registration for all Americans and a new national standard of at least 20 days of early in-person voting in every state.

With the 2016 presidential race ramping up, voting-rights issues are likely to take center stage as advocates press for changes and try to educate voters.

While several members of Congress from both parties have backed new legislation to update the landmark 1965 law, those efforts have stalled in the Republican-led Congress. The legislation was filed in response to the Supreme Court's 2013 ruling that overturned a provision of the Voting Rights Act that required certain states with a history of racial discrimination at the polls to "pre-clear" any changes to the law with the federal government before implementing them.

Sewell represents Selma, Alabama, the city made famous by the brutal attack on voting rights protests in 1965, known as Bloody Sunday. She said the move would disproportionally impact her constituents in the 7th Congressional District and that the state should either rescind its requirement for voter IDs at the polls -- which she likened to past discriminatory practices such as poll taxes and literacy tests -- or allow the driver's license offices to stay open.

She wrote than an estimated 250,000 Alabamians do not have an acceptable form of photo identification to cast a ballot and argued the DMV closures "further exasperate this tenuous situation."

While nearly a dozen forms of ID are accepted -- including a U.S. passport, a military ID and a tribal ID -- Sewell noted that a driver's license is the most popular form of ID used at polling stations.

"To limit access to obtaining a driver's license -- while insisting on a photo ID to vote -- is an unconscionable and overt barrier to voting," she said. "Twenty-nine counties in Alabama will have no driver's license offices, of which 15 of those counties are located in the rural parts of the Black Belt. This fact means many of my constituents who have limited modes of transportation will be denied an equal opportunity to obtain a means to vote."

The Alabama Law Enforcement Agency announced last week that an $11 million cut in the budget would force the closing of 31 part-time, county-owned satelllite locations at which residents can obtain or renew their licenses. The state expects some of the needs of those who would have used such offices to be met online.

"In July, I announced several advancements that will help the driver license issuance process, including online scheduling, online driver license renewals and duplicates, self-serve kiosks, digital licensing for smart phones, and statewide equipment upgrades. Since making that announcement, we have had over 40,000 transactions online," Secretary of Law Enforcement Spencer Collier said. "The impact of the changes due to the budget cuts will be lessened because of the implementation of these technology-based services, including online renewals."

Alabama issues an average of 1.2 million driver's licenses each year and says the Driver License Division is "severely understaffed and has 103 vacant positions as a result of past budget cuts and attrition," Collier's statement read. He added that an analysis found the 31 part-time locations accounted for less than 5% of all state driver's license transactions performed by ALEA, with the busiest location performing fewer than 2,000 transactions last year.

Sewell said online access would not be sufficient.

"I'm highly disappointed that our state officials assume that just because you can go online that people who live in poor rural communities actually have a computer and can do that," said Sewell, who sponsored one of the bills aimed at updating the 1965 law.

The congresswoman said the consequences of the agency's decision "is to deny the most vulnerable in Alabama an equal opportunity to obtain a means to vote," potentially disenfranchising poor, elderly, disabled and black residents and those with limited access to transportation."