ANCHORAGE — Scores of Alaskans have complained about receiving emails and letters to find their voting histories and those of their acquaintances sent by an elusive group calling itself the Alaska State Voter Program.

The messages say the super PAC-backed group plans to update the lists following next week’s election. One voter, Cheryl Alsip, said she is furious and feels the group is trying to shame people into voting. Alsip, 57, is a Vietnam veteran who believes it’s important to vote, but she is disabled and homebound in the small interior Alaska town of Salcha.

“I believe in this country. I fought for this country,” Alsip, a registered Republican, said. “I want my voice heard in one way or another.

But whether she voted, and when?

“It’s nobody else’s damn business.”

Stakeholders in the midterm elections are trying to boost voter turnout in contests like Alaska’s that could help determine control of the Senate.

Similar pressure tactics have been employed elsewhere, including postcard mailers in Arkansas, where Sen. Mark Pryor is defending his seat against a strong challenge from Republican Rep. Tom Cotton. In Louisiana, the conservative group funded by the billionaire Koch brothers, Americans For Prosperity, sent postcard mailers in the battle for the seat held by Democratic Sen. Mary Landrieu.

In Alaska, Democratic Sen. Mark Begich is struggling to hold off a challenge from Dan Sullivan, and turnout there is a particular challenge give the state’s size and climate.

The Alaska messages are sponsored by the Opportunity Alliance PAC. John Bryan of Lake Oswego, Oregon, contributed $200,000 to the PAC, but said he didn’t know it would pay for the vote-shaming letters and emails in Alaska. Bryan is the founder of the Plano, Texas, based nonprofit Challenge Foundation, which supports the start-up of charter schools around the country, as well as the affiliated TeamCFA, based in Lake Oswego. He said he personally contributes to conservative causes.

This year, his goal was to support Republican U.S. Senate candidates, he said.

“I hope the Republicans gain control of the Senate,” Bryan told The Associated Press. “I want to be quite clear about that.”

Opportunity Alliance PAC treasurer Cabell Hobbs said Wednesday he just handles the accounting and the Federal Election Commission filings, and had no further comment, including if the PAC is conservative or who is behind it.

Both conservative and liberal groups have employed mailers about voter histories. In 2012, the left-leaning political organization Defend Oregon sent postcards to residents, showing how their voting participation stacked up against their neighborhood average. USA Today also reported in 2012 that the liberal group MoveOn sent similar vote scores to potential progressive voters. In both cases, voting histories of neighbors were not listed.

The letter Alsip received over the weekend arrived in an envelope with a red arrow pointing to the inscription: “IMPORTANT TAXPAYER INFORMATION ENCLOSED.”

There was no tax information.

“Why do so many people fail to vote? We’ve been talking about the problem for years, but it only seems to get worse,” the letter states. “This year, we’re taking a new approach. We’re sending this mailing to you, your friends, your neighbors, your colleagues at work, and your community members to publicize who does and does not vote.”

The Alaska voter group’s website says, “We’re advertising to you and your friends and neighbors to publicize who does and does not vote.” The letters and emails are not signed, and there is no listing in the state for the group. An email seeking comment from the group was not returned. The Anchorage address listed on the envelope Alsip received is a mail box service.

State elections director Gail Fenumiai said Tuesday her office has received several dozen complaints from voters who received the messages from the group, which purchased a statewide voter list from the state for $21. At least one voter registration with the state has been canceled because of the messages, according to Fenumiai.

“We’ve never seen the state list used in such an invasive manner,” she said. “People are very upset by it. It is public information, but the way they’ve used it is above and beyond anything we’ve ever seen before.”

Her office is giving voters a Washington, D.C., number affiliated with the group, which did not return a call from The Associated Press.

There’s nothing illegal about the messages because state law doesn’t put any limitations on what can be done with the voter lists. Fenumiai said any limits placed would have to come from state legislators.

Alsip, who also received two emails from the group, said she plans to contact lawmakers to implement those changes. She hopes other Alaskans to the same.

Beyond being angry about the letter, “I feel humiliated,” she said about being targeted. “I feel intimidated.”