The relatively few votes at stake _ only a few hundred _ mean the drive's potential to affect outcomes this fall on such issues as gay marriage, marijuana laws and tax limits is low.
Though prison inmates tend to skew to the Democratic side, the drive isn't about furthering any political agenda, said Rachel Talbot Ross, president of the Portland chapter of the National Association for the Advancement of Colored People.
"It's about establishing strong voter patterns and becoming a fully functioning person to re-enter society," Ross said. "It's part of the rehabilitation and re-entry process."
The NAACP is wrapping up its effort in Maine prisons this week. After next June's primary election, the organization plans to lead another drive at all 15 county jails, as well as state prisons.
It's not focusing just on black inmates.
Volunteers already have registered an estimated 200 or more inmates at five of the state's seven adult correctional centers. The Maine State Prison's NAACP chapter _ the only one of its kind in New England _ has 70 members, many of them white, including the branch president, Ross said.
Randal Horr, a 49-year-old white inmate at the Bolduc minimum-security prison in Warren, registered as a Democrat when volunteers arrived. Going through the voting process helps him feel connected to the outside world and will help when he is released, he said.
In November's election, he said, he plans to vote for state and municipal tax and spending limits and liberalizing medical marijuana laws. He's not sure how he'll vote on whether to overturn a state law allowing gay marriage.
"Having that access to the vote makes a difference. It makes me feel I'm continuing in the loop of the community and society. You feel like you count," said Horr, who has served nearly nine years of an 11 1/2-year sentence for habitual drunken driving.
State laws giving convicted felons the right to vote vary. About 5.3 million people nationwide are barred from voting because of criminal convictions, according to the American Civil Liberties Union.
Only in Maine and Vermont are felons in state prisons allowed to cast ballots while serving their sentences. Those prisoners, however, still have to register to vote, something easier done on the outside.
To help those inmates, the NAACP last year held a drive at the Maine State Prison, the Maine Correctional Center in Windham and the Cumberland County jail in Portland.
The effort now under way is the first time there's been a systemwide initiative to register inmates across an entire state, Ross said. Benjamin Jealous, national NAACP president, was on hand last week as volunteers registered inmates at five correctional centers.
Inmates are prohibited from hanging political signs in their cells or even wearing political buttons, said Denise Lord, Maine's associate corrections commissioner. But officials encourage inmates to vote, she said.
"When someone is engaged in social activities, thinking of others or outside of themselves, that is what we would call a positive behavioral development," she said. "Registering to vote is one indication of that."
State Sen. Chris Rector, R-Thomaston, gave a quick presentation of the Republican platform to a group of inmates before helping register them last week at the Bolduc prison, where Horr learned about his options.
"They say recidivism rates are lower among those who can achieve some kind of community engagement," Rector said. "This is a tiny building block in that process."