Editor’s note: One in a frequent series of stories examining Maine’s voting system.

Almost half of all American voters believe they will have some trouble as they try to cast their ballots in the Nov. 3 presidential election.

The Pew Research Center drew that conclusion after a survey in July and August of 11,001 U.S. adults, including 9,114 registered voters. High on the list of concerns is what happens if they show up at the polls and learn they are no longer on the voter list.

Election officials, usually town or city clerks in Maine, are required to maintain accurate lists of registered voters. To that end they follow a complex list of rules over when and how a voter can be removed or “purged” from a voting list.

Here’s what you need to know about how Maine maintains its voter lists and when voters can be purged from the list of registered voters:

When can voters be removed from a voter list?

Voting lists are maintained under a myriad of state and federal laws, and their requirements vary widely. But in Maine, you can be removed from a voting list only under specific circumstances, including:

• Death. Clerks can remove you from their list if they receive notice that you have died, including receipt of a death certificate or notice of an obituary announcing your death.

• You ask in writing to be removed from the voting list.

• The clerk receives notice that you have registered to vote in a new city or town.

• The clerk receives notice that you have requested a name or address change in connection with a motor vehicle registration, and you have moved outside of the municipality. If you have moved within the municipality the clerk will update your voter information but you will remain a registered voter.

• If the clerk receives a pre-printed U.S. Postal Service change of address request that you have signed and your new address is outside the municipality.

• A response to a change of address notification card. A clerk can remove you from the voter list if you respond to this notification and confirm you have moved outside of the municipality.

• If a clerk receives other notice or information from you, including your new address and signature, they may remove you from the voting list.

What should I do if I haven’t voted in awhile?

If you haven’t voted in the last two federal elections, 2016 and 2018, or you have recently moved, married or otherwise changed your legal name or address, you should make sure you are registered to vote by checking with your town or city clerk now. Election officials are urging voters to not wait until Election Day to find out if they need to re-register.

While registration on Election Day is allowed in Maine, clerks say it will slow the voting process and add to traffic in polling places – all operating under tight restrictions, including occupancy limits, aimed at protecting against the spread of COVID-19.

Where have voter purges taken place recently?

In 2016, an infamous case unfolded in New York City, where a mistaken purge in the borough of Brooklyn left some 200,000 voters in limbo during an April presidential primary election. Likewise, some 7,700 voters in Arkansas were inappropriately removed from the voting lists for being convicted felons – even though many of them were not – while others had their voting rights previously restored, according to a 2019 report by New York University’s Brennan Center for Justice.

But what about Maine?

Maine was flagged in the same Brennan Center for Justice report for the way it used a national voter registration crosscheck system to remove voters from its voting lists, but state officials say that process is no longer in place.

What does it mean if my voter registration is designated “inactive?”

Maine law allows, but does not require, local clerks to maintain a list of inactive voters. An inactive voter is somebody who has not participated in at least two consecutive federal elections.

You cannot be designated an inactive voter if you have otherwise participated in the election process, such as by signing a petition for a local or statewide ballot measure, or signing a nominating petition for a candidate running for public office.

If you are designated inactive, before you can be removed from the voting list election officials must send you a change-of-address confirmation card. If you respond saying you have not moved, your voting record will remain active.

What if I don’t respond?

If you don’t respond, your record will remain inactive but you will not be removed from the voting list. The lists of inactive voters are shared to the state’s Central Voter Registry. Information in the registry can be sold for use by parties, candidates, campaigns and get-out-the-vote organizations. The general public has only limited access to information in the registry.

How many inactive voters are there in Maine?

Currently, of the state’s more than 1.06 million registered voters, only 3,847 are listed as inactive. None of Maine’s three largest cities – Portland, Lewiston and Bangor – shows any inactive voters on its voting lists.

How else are inactive lists used?

State law also requires a periodic update of municipal voting lists — every five years. The next update for Maine will be in 2021. During those reviews clerks can send a mass mailing to all inactive voters with change-of-address confirmation cards. If a voter does not respond and then does not participate in the next two federal election within the municipality, the clerk can then remove the voter from the voting list.

What happens if I go to vote and officials tell me I’m not registered?

Don’t panic. Because of Maine’s same-day registration law, you can register and vote on Election Day. And while you don’t need a photo ID to vote, it makes things easier – if you have one – to register to vote. But you can also register using other identity documents in combination, such as your birth certificate or social security card with proof of residency, such as a bill from a utility company showing your current address, or a paycheck stub with your home address.

What if I don’t remember to bring any of that to the polling station?

Still no need to worry. If you cannot provide the appropriate documents that allow you to register to vote, you will be allowed to cast a challenge ballot. Your ballot will be cast and counted with the other ballots, but it is coded in a way that allows it to be removed from the tally if there is a question in the outcome of the election. You will still be required to provide proof of your identity and residency after the election or you will be removed from the voter list and not allowed to register to vote until you can provide that documentation.

How does Maine’s purge rate stack up?

In 2016, the statewide purge rate was 15 percent of Maine’s voting age population, according to a survey by the U.S. Election Assistance Commission published by ProPublica. The purge rates varied from one municipality to another, including Portland with a 21 percent rate, Bangor with 18.8 percent, Augusta with 16.9 percent, Waterville with 15.5 percent and Biddeford with 17.8 percent.

Secretary of State Matthew Dunlap said purge rates in Maine sometimes appear to be high because the published data often reports only how many voters have been removed from a voting list without accounting for the transfer of voters to other municipalities or voting jurisdictions.

Maine has among the highest rates of voter registration in the nation, with about 96 percent of the state’s eligible voters registered to vote, Dunlap said.

Overall, Dunlap said the purging of voting lists, “Isn’t something that people in Maine should lay awake at night worrying about.”

Purges are more of a factor in states with laws that require voters be registered by a certain deadline ahead of an election. In those states, voters who find they’ve been removed from a voting list after a voter registration deadline could face the prospect of being disenfranchised on Election Day.

Correction: This story was updated at 11:38 a.m. on Sept. 24, 2020, to correct the identity documents you may use to register to vote. It was updated at 6:15 p.m. on Sept. 24, 2020, to remove an incorrect circumstance for being removed from a voting list and to provide correct information about casting a challenge ballot.

Next: Why aren’t absentee ballots available before Oct. 3?

Do you have a question about Maine’s election system or how your vote will be counted? Send it to countingvotes@pressherald.com