(CNN) As the polls opened this week in Georgia for the first day of in-person early voting, telephones were buzzing inside the state Democratic party's "voter protection" war room in downtown Atlanta.

The operation, which has been promoted for months now by the party and Democrat Stacey Abrams' gubernatorial campaign, connects rows of trained volunteers with callers asking about anything from polling locations to a controversial protocol that has left tens of thousands of voters in legal limbo.

Those "pending" registrations became a flashpoint last week when an Associated Press report revealed that 53,000 registrations, nearly 70% of them belonging to African Americans, had been held up under "exact match," a law championed by the office of Secretary of State Brian Kemp -- Abrams' Republican opponent.

Kemp's perennial clashes with civil rights and Democratic groups -- and his record of purging 1.5 million voters from Georgia's rolls between the 2012 and 2016 elections, according to a report from the Brennan Center for Justice -- set the tone for the race from early on in the year. The AP report, followed days later by a new lawsuit against Kemp's office, has driven national attention to a state that has not elected a Democrat governor since 1998. Abrams, who is running an audaciously progressive campaign, would be the first African American woman ever elected to the office, in Georgia or anywhere else.

"Hotlines like this are oftentimes seen in battleground states during presidential election years," said Rebecca DeHart, the state Democratic party's executive director. "This is a bit more rare in a midterm election and it is, by far, the first time the state of Georgia has done anything of this magnitude."

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