Each year, New Hampshire’s political parties spend thousands of dollars to obtain key information: voters’ names, addresses, and the real gold mine, their party affiliation.

It’s all public information – anyone can go to the State Archives in Concord and crack a peek at the voter checklists from various elections – but parties, political action committees and candidates can purchase it as a database for their own use.

The New Hampshire Democratic Party and the NH Democratic Federal Account have purchased the statewide voter roll a combined 43 times for a total of $345,159.50 over the past 10 years as of July, according to state records. The New Hampshire Republican State Committee bought it 41 times, totaling $295,490 in the past decade.

Chris Ager, the Republican committee chairman, said the information is worth it and saves time, money and manpower by tailoring outreach efforts.

“It’s kind of like the Bible of voter contact,” Ager said.

Here’s how it works: Anyone who registers to vote – whether they actually vote or not – is added to their local voter checklist. This roll includes a voter’s first, middle and last name, their home address and their registered party. On Election Day, poll workers write a check mark by the name of each person who voted and add same-day voter registrations to the list. It doesn’t detail who or what party received their vote.

If a voter hasn’t declared a party affiliation, it’ll show that, too – that’s who Ager said his team courts the most. The New Hampshire Democratic Party didn’t respond to multiple interview requests for this story.

Ager said the voter checklist helps the committee identify who’s likely to vote and undecided voters who might be swayed to cast a ballot for their candidates, effectively narrowing down their targets for campaign mailers and door-knocking efforts.

“The solid Republicans, the solid Democrats, it’s more of a get-out-the-vote campaign. As long as they vote, you feel pretty good they’re going to vote for your side,” Ager said. “The ‘undeclareds’ are the ones that you may want to do more persuasion to, so it’s very helpful in that regard – not only target ‘who,’ but also with what type of message.”

New Hampshire has sold its voter checklists – ranging from singular towns and districts to statewide – nearly 200 times in the past decade to a variety of recipients. In addition to the state and local branches of the major political parties, other buyers include presidential campaigns, dozens of down-ballot candidates and political action committees. Some groups purchase it regularly, like Free State Data, the Granite State Freedom PAC and a progressive data group called Catalist for Change, according to the state records. PACs and advocacy groups have spent more than $438,000 on New Hampshire voter checklists since 2014.

Pricing varies, but the cost of the statewide voter roll hovers around $8,300. The same sort of checklist exists for absentee voters – that typically costs $2,000.

The database comes with some rules about what parties and candidates can do with voter information. Since it’s publicly available, they can share the information with whoever they want, Secretary of State David Scanlan said. The main restriction is that it can’t be used for commercial purposes. People can use it to solicit votes, or nonprofit organizations can use it to increase their membership, but it can’t be used to sell anything.

Scanlan said some people get concerned that their information is public when they vote, but that’s the ball game.

“If you’re going to participate in an election, the other voters that are participating have a right to know who is participating in the election,” Scanlan said. “The checklist is the record of that.”

New Hampshire has made more than $1.1 million in the past decade from sales of the voter checklist. Scanlan said the state cycles that revenue back to towns, which funds the upkeep and management of each locality’s database.

A change in state law that went into effect Oct. 1 allows down-ballot candidates to request one free copy of their local voter checklists, which will eliminate the cost for candidates running in smaller districts. Compared to the statewide voter roll, the lists by district only cost a few hundred dollars, if that. It won’t apply to the statewide lists.

Ager said there are some challenges with the checklist: People move, or sometimes they don’t vote along party lines. For the most part, though, he said that information is invaluable. He compared it to a quote from a famous early-20th century bank robber.

“He was asked, you know, ‘Why do you rob banks?’ And his answer was, ‘Because that’s where the money is,’” Ager said. “It’s kind of the same thing with the voter files.”

Charlotte Matherly is the statehouse reporter for the Concord Monitor and Monadnock Ledger-Transcript in partnership with Report for America. Follow her on X at @charmatherly, or send her an email at cmatherly@cmonitor.com.