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A group that tries to get “historically underrepresented groups” to the polls has targeted some particularly unlikely voters: dogs and dead Virginians.

Early-afternoon voters at Popes Head Precinct in Fairfax in August 2011. Election officer Dave Mitchell, right, shows the Courtney family how to use the voting machine. (Tracy A Woodward/The Washington Post)

The mailings have revived talk of voter fraud in Virginia, a crucial swing state where President Obama and Republican candidate Mitt Romney are deadlocked in a recent poll. And it has prompted the Romney campaign to call for a criminal investigation.

“This presents a very significant risk to the proper administration of the upcoming general election,” Kathryn Biber, the campaign’s general counsel, said in a letter sent Tuesday to Attorney General Ken Cuccinelli II (R) and the State Board of Elections.

The center said it used a commercial mailing list to target unregistered voters, and that it never meant to send forms to anyone ineligible to vote. It said the errant mailings, first reported by the Richmond Times-Dispatch, represent just a fraction of the nearly 200,000 it sent out across Virginia.

“The state forms are official applications, they are not registration cards,” the center said in a written statement issued Wednesday. “Furthermore, they were approved by the State Board of Elections before we sent them out and are the same applications that anyone can access at a local government office or on the Internet. Our process is legal and working.15,000 Virginians have submitted these registration applications and been added to the rolls by government officials - a start at whittling down the state’s 2 million unregistered [voters].”

But for some, the mailings have reignited fears that Virginia is vulnerable to voter fraud, a claim that was bitterly debated in the General Assembly this year. Citing concerns about the integrity of elections, the GOP-controlled General Assembly closed a loophole that had allowed voters to cast ballots without showing identification. Democrats charged that the voter ID law, while more moderate than those Republicans have recently pushed in other states, was intended to make it harder for minorities and other Democratic-leaning groups to vote.

State Sen. Thomas Garrett (R-Louisa), a Louisa County prosecutor who successfully tried two felons who registered to vote in 2009, said one of the two registered after receiving a form by mail from the Voter Participation Center.

“Clearly they haven’t gotten the message,” Garrett said.

Page Gardner, the center’s president, said the center was only trying to encourage eligible voters to exercise their franchise. She said the group tries to make its mailing list “as perfect as possible.”

“We have nothing to do with that issue, voter fraud. We send people applications to fill out in the mail,” Gardner said. “It’s up to them to fill out the form and obey all the state laws and federal laws.”

The dead can wind up on a mailing list because it is compiled from things such as magazine subscriptions, which often are not updated with a new name when a spouse dies. Some people have subscriptions in the names of their pets for reasons that Gardner, who described herself as “a non-pet owner,” said she did not understand.

The focus on the errant mailings is a “man-bites-dog story” in Gardner’s view, one that she says misses the bigger picture — that nearly 2 million eligible Virginians are not registered to vote.

“It’s fun to write about Mozart and other pets getting these voter registration applications,” Gardner said, referring to a dead dog who was sent a form from her group. “[But] at some point, we have to look at ourselves and say, ‘Really, what’s the story here?’ ”

In her letter, Biber contends that the center’s mass mailing may have violated state laws, including those that prohibit falsifying a registration application and communicating false information to voters about their registration status.

“The conduct of the Voter Participation Center likely violates at least one and maybe several Virginia laws aimed at ensuring a fair election,” the letter says. “The Center’s conduct is all the more troubling because the Center’s materials affirmatively tell mailing recipients that ‘records show that you are eligible to vote in the 2012 presidential election.’ ”

Biber also contends that the center violated the law by “pre-populating” the registration forms, meaning it filled in the names on applications. She contends that only voters, not a third party registering them, may fill out the application.

Biber also asks the State Board of Elections to review the eligibility of everyone registered to vote in the past two months.

“This is the only way for voters and other interested parties to regain confidence in the voter registration and electoral process that has been abused by the Voter Participation Center,” she wrote.

State elections officials and Cuccinelli’s office did not immediately respond to requests for comment.